University  of  California  •  Berkeley 

SIDNEY  HOWARD  COLLECTION 

Gift  of 
The  Family  of  Sidney  Howard 


SIDNEY 

HOW/      » 


PREFACE. 


The  results  of  the  work  of  Maj.  Walter  Reed,  Medical  Corps, 
United  States  Army,  and  the  Yellow  Fever  Commission,  of  which  he 
was  president  and  the  masterful  mind,  have  been  so  beneficial  and 
far-reaching  that  its  importance  is  considered  secondary  to  no  other 
scientific  achievement. 

The  various  publications  in  regard  to  Maj.  Reed  and  his  work  and 
the  reports  of  the  commission,  as  well  as  other  reports  on  subjects 
intimately  connected  with  this  work,  while  all  extant  and  on  file  in 
the  larger  libraries  of  this  country,  are  not  available  for  the  profes- 
sion in  general.  Being  bound  in  one  volume  they  will  be  much  more 
available  for  general  use,  and  will  be  less  liable  to  be  misplaced. 

Many  of  the  younger  men  in  the  profession  and  in  the  Medical 
Corps  of  the  Army  are  not  so  thoroughly  conversant  with  the  various 
steps  of  this  work  as  is  thought  desirable.  This  work  should  be  a 
source  of  inspiration  for  every  medical  officer. 

In  compiling  these  various  publications  repetitions  have  been 
avoided  as  much  as  possible.  However,  the  reports  of  Maj.  Reed 
and  his  associates  are  considered  of  so  much  scientific  as  well  as  his- 
torical interest  that  they  are  published  in  full  in  chronological  order. 
In  this  way  the  various  steps  in  the  experiments  are  more  clearly 
shown. 

3 


I 


TABLE  OF  CONTENTS. 

Page. 

PART  I. — Walter  Reed,  the  man,  his  work,  and  the  appreciation  shown  of  the 
results  accomplished  by  him  and  his  associates  on  the  Yellow  Fever  Commis- 
sion: 

Chapter  1.  A  memoir 7 

Chapter  2.  Sketch  of  the  life  of  Maj.  Walter  Reed 14 

Chapter  3.  Message  from  the  President  of  the  United  States,  December  5, 
1906,  embodying  letter  from  Brig.  Gen.  R.  M.  O'Reilly,  Surgeon  General 

United  States  Army 17 

Chapter  4.  Senate  Document  No.  520,  Sixty-first  Congress,  second  session, 
embodying  letter  from  Brig.  Gen.  George  H.  Torney,  Surgeon  General 

United  States  Army 24 

Chapter  5.  In  memoriam;  District  of  Columbia  Medical  Society 32 

Chapter  6.  Value  of  Dr.  Reed's  work  and  expressions  of  appreciation 48 

PART  II. — The  publications  of  Walter  Reed  and  his  associates  on  the  commis- 
sion in  regard  to  yellow  fever: 
Chapter  1.  Bacillus  icteroides  and  Bacillus  cholenv  suis — A  preliminary  note, 

April  1,  1899 53 

Chapter  2.  The  Etiology  of  Yellow  Fever — A  preliminary  note,  October, 

1900 56 

Chapter  3.  The  Etiology  of  Yellow  Fever — An  additional  note,  February, 

1901 70 

Chapter  4.  The  Propagation  of  Yellow  Fever — Observations  based  on  recent 

researches,  April,  1901 90 

Chapter  5.  Experimental  Yellow  Fever,  May,  1901 110 

Chapter  6.  The  Prevention  of  Yellow  Fever,  September,  1901 131 

Chapter  7.  The  Etiology  of  Yellow  Fever — A  supplemental  note,  January, 

1902 149 

Chapter  8.  Recent  Researches  Concerning  the  Etiology,  Propagation,  and 
Prevention  of  Yellow  Fever,  by  The  United  States  Army  Commission 

(three  charts),  April,  1902 161 

PART  III. — The  publications  of  James  Carroll,  assistant  surgeon,  United  States 
Army,  in  regard  to  yellow  fever  (published  after  the  death  of  Maj.  Reed): 

Chapter  1.  The  Transmission  of  Yellow  Fever,  May,  1903 175 

Chapter  2.  Remarks  on  the  Epidemic  of  Yellow  Fever  in  Baltimore,  Feb- 
ruary, 1905 186 

Chapter  3.  Yellow  Fever— A  popular  lecture,  April,  1905 195 

Chapter  4.  Lessons  to  be  Learned  from  the  Present  Outbreak  of  Yellow 

Fever  in  Louisiana,  September,  1905 216 

PART  IV. — Reports  from  sanitary  officers  in  Habana,  Cuba,  demonstrating  the 
practical  value  of  the  scientific  findings  of  Maj.  Reed  and  his  associates  on  the 
Yellow  Fever  Commission: 

Chapter  1.  Report  of  Col.  Valery  Havard,  February,  1901 221 

Chapter  2.  Report  of  Charles  Finlay,  chairman  of  the  Habana  Yellow  Fever 

Commission,  January,  1902 227 

Chapter3.  Report  of  Maj.  W.  C.  Gorgas,  Medical  Corps,  United  States 

Army,  July,  1902 234 

PART  V.— A  few  general  directions  with  regard  to  destroying  mosquitoes,  par- 
ticularly the  yellow-fever  mosquito,  by  Col.  William  C.  Gorgas,  Medical 

Corps,  United  States  Army 

5 


I 


PART  I —WALTER  REED— THE  MAN,  HIS  WORK,  AND  THE  APPRECIA- 
TION SHOWN  OF  THE  RESULTS  ACCOMPLISHED  BY  HIM  AND  HIS 
ASSOCIATES  ON  THE  YELLOW  FEVER  COMMISSION, 


CHAPTER  1. 

WALTER  REED.— A  MEMOIR.1 

By  WALTER  D.  MC€AW,  Major,  Medical  Corps,  United  States  Army. 

It  is  given  to  but  few  scientific  men  to  lay  bare  a  secret  of  nature 
materially  affecting  the  prosperity  of  nations,  and  the  lives,  fortunes, 
and  happiness  of  thousands.  Fewer  still  succeed  in  so  quickly  con- 
vincing brother  scientists  and  men  in  authority  of  the  truth  of  their 
discoveries  that  their  own  eyes  behold  the  glorious  result  of  their 
labor. 

Of  the  51  years  of  Walter  Reed's  industrious,  blameless  life,  12 
only  were  spent  in  the  study  of  the  special  branch  of  science  in  which 
he  became  famous,  but  his  name  now  stands  with  those  of  Jenner, 
Lister,  and  Morton  as  among  the  benefactors  of  humanity. 

Walter  Reed  was  born  in  Gloucester  County,  Va.,  September  13, 
1851,  the  son  of  the  Rev.  Lemuel  Sutton  Reed  and  Pharaba  White, 
his  wife. 

The  circumstances  of  his  family  were  modest,  and  some  of  the 
years  of  his  boyhood  were  spent  in  a  much  troubled  section  of  the 
south  during  the  great  Civil  War.  He  acquired,  however,  a  good 
preliminary  education,  and  at  an  age  when  most  boys  are  still  in 
the  schoolroom  he  began  the  study  of  medicine  at  the  University  of 
Virginia,  graduating  as  M.  D.  in  1869,  when  only  17  years  old. 

A  second  medical  degree  was  received  later  from  Bellevue  Medical 
College,  New  York,  and  then  came  terms  of  service  in  the  Brooklyn 
City  Hospital,  and  the  City  Hospital,  BlackwelFs  Island. 

Before  the  age  of  21  Reed  was  a  district  physician  in  New  York 
City,  and  at  22  one  of  the  five  inspectors  of  the  board  of  health  of 
Brooklyn. 

He  entered  the  Army  of  the  United  States  as  assistant  surgeon 
with  the  rank  of  first  lieutenant,  in  1875,  and  for  the  next  18  years, 
with  the  usual  varying  fortunes  of  a  young  medical  officer  of  the 
Army,  he  served  in  Arizona,  Nebraska,  Dakota,  and  in  the  Southern 
and  Eastern  States. 

According  to  the  exigencies  of  the  service  he  was  moved  frequently 
from  station  to  station,  everywhere  recognized  by  men  of  his  own 
age  as  a  charming  and  sympathetic  companion,  and  by  older  officers 

1  Washington,  D.  C.    Published  by  the  Walter  Reed  Memorial  Association,  1904. 

7 


as  an  earnest  and  intelligent   physician,  whose  industry,   fidelity  to 
duty,  and  siniri:.  U  judgment,  gave  brilliant    promise  for'  the 

future.  In  the  pom  cabins  and  dugouts  of  the  pioneers  in  the 
sparsely  settled  districts  where  he  served  his  flag,  Reed  was  ev« 
messenger  of  healing  and  comfort.  At  that  time  Army  posts  on  the 
frontier  were  usually  remote  and  with  small  irnrrisons.  The  vounir 
medical  oihcer,  generally  the  only  one  at  the  station,  was  called  upon 
bythesr  -r  mitos  around.  \Vithout  help,  and  with  only  such 

instruments  and  medicines  as  could  be  hastily  stuffed  in  his  saddle 
he  was  summoned  to  attend  a  fractured  thi«rh,  a  child  choking  \\ith 
diphtheria,  or,  most  mint:  of  all,  a  complicated  childhirth. 

Such  experience  BCOOOb  \\ell  in  self-reliance,  and  in  the  formation 
of  quick  and  accurate  observation. 

For  a  man  like  Reed,  already  an  earnest  student,  no  better  p 
tion  could   perhaps  have  been   had.      His  earlier  Army  must 

have  singularly   tended  to  develop  in   him   the  very  (pialities   i 
necessary  to  his  final  success.     To  the  end  of  his  life  il  \\.  -able 

that  even  when  he  had  long  given  up  the  practice  of  medicine  for  the 
work  of  the  laboratory,  he  was  nevertheless  unexcelled  at  t  he  bedside 
for  rapid,  unerring  diagnosis  and  sound  iii<l«unent  in  treatment. 
also  were  the  series  of  experiments  which  robbed  yellow  fever  of  its 
terrors  especially  remarkable  for  simplicity,  accuracy,  and  complete- 
ness, or  they  never  would  have  so  quicldy  convinced  the  won 
their  truth.     Too  much  reverence  for  accepted  teachings,  am: 
little  experience  in  grappling  with  difficulties  unassisted,  and  they 
might  never  have  been  conceived  or  carried  out. 

In  1890  he  was  assigned  to  duty  in  Baltimore  and  remained  t 
over  a  year.     Here  he  had  the  great  advantage  of  working  in  the 
laboratories  of  Johns  Hopkins  University  and  the  happiness  of  win- 
ning the  close  friendship  of  his  distinguished  teacher,  JProf.  William 
II.  Welch. 

In  1893,  Reed  was  promoted  surgeon  with  the  rank  of  major. 
and  in  the  same  year  was  detailed  in  Washington  as  curator  of  the 
Army  Medical  Museum  and  professor  of  bacteriology  at  the  newly 
organized  Army  Medical  School.     Here  he  worked  industrious) 
his  specialty   and   wrote  many  valuable  monographs,   all   ch. 
terized  by  accuracy  and  originality.     His  excellent  judgment  made 
him  especially  valuable  in  investigating  the  causes  of  epidemic  dis- 
eases at  military  posts,  and   in   making  sanitary  inspections.      He 
was,  therefore,  frequently  selected  for  such  work,  which  with   his 
duties  as  teacher  and  member  of  examining  boards,  occupied  much 
of  the  time  that  he  would  otherwise  have  spent  in  his  la! 
1  i «  i  e  again  it  seems  that  duties  which  must  often  have  1  lome 

were  specially  fitting  him  for  his  culminating  work. 

During  the  Spanish-American  war  the  camps  of  the  volunteer 
troops  in  the  United  States  were  devastated  by  typhoid  f< 
Mai.  Reed  was  selected  as  the  head  of  a  board  to  study  the  causat  ion 
and  spread  of  the  disease.     This  immense  task  occupied  more  than 
a  year's  time.     With  the  utmost  patience  and  accuracy  the  details 
of  hundreds  of  individual  cases  were  grouped  and  studied.     The 
report  of  the  commi  —  ion.  now  in  course  of  publication  by  the  < 
eminent,  is  a  monumental  work  which  must  always  serve  as  a  basis 
for  future  study  of  the  epidemiology  of  typhoid  fever. 


YELLOW    FEVER.  9 

The  most  original  and  valuable  work  of  the  board  is  the  proof 
that  the  infection  of  typhoid  fever  is  spread  in  camps  by  the  com- 
mon fly,  and  by  contact  with  patients  and  infected  articles,  clothing, 
tentage,  and  utensils,  as  well  as  by  contaminated  drinking  water. 

In  June,  1900,  Maj.  Reed  was  sent  to  Cuba  as  president  .of  a  board 
to  study  the  infectious  diseases  of  the  country,  but  more  especially 
yellow  fever.  Associated  with  him  were  Acting  Asst.  Surgs.  James 
Carroll,  Jesse  W.  Lazear,  and  A.  Agramonte. 

At  this  time  the  American  authorities  in  Cuba  had  for  a  year  and 
a  half  endeavored  to  diminish  the  disease  and  mortality  of  the  Cuban 
towns,  by  general  sanitary  work,  but  while  the  health  of  the  popu- 
lation showed  distinct  improvement  and  the  mortality  had  greatly 
diminished,  yellow  fever  apparently  had  been  entirely  unaffected  by 
these  measures.  In  fact,  owing  to  the  large  number  of  nonimmune 
foreigners,  the  disease  was  more  frequent  than  usual  in  Habana  and 
in  Quemados  near  the  camp  of  American  troops,  and  many  valuable 
lives  of  American  officers  and  soldiers  had  been  lost. 

Reed  was  convinced  from  the  first  that  general  sanitary  measures 
alone  would  not  check  the  disease  but  that  its  transmission  was  prob- 
ably due  to  an  insect. 

The  fact  that  malarial  fever,  caused  by  an  animal  parasite  in  the 
blood,  is  transmitted  from  man  to  man  through  the  agency  of  certain 
mosquitoes  had  been  recently  accepted  by  the  scientific  world;  also 
several  years  before  Dr.  Carlos  Finlay,  of  Habana,  had  advanced  the 
theory  that  a  mosquito  conveyed  the  unknown  cause  of  yellow  fever, 
but  did  not  succeed  in  demonstrating  the  truth  of  his  theory. 

Dr.  H.  R.  Carter,  of  the  Marine-Hospital  Service,  had  written  a 
paper  showing  that  although  the  period  of  incubation  of  yellow  fever 
was  only  5  days,  yet  a  house  to  which  a  patient  was  carried  did 
not  become  infected  for  from  15  to  20  days. 

To  Reed's  mind  this  indicated  that  the  unknown  infective  agent 
has  to  undergo  a  period  of  incubation  of  from  10  to  15  days,  and 
probably  in  the  body  of  a  biting  insect. 

Up  to  this  time  the  most  generally  accepted  theory  as  to  the  causa- 
tion of  yellow  fever  was  that  of  Sanarelli,  who  claimed  that  the 
Bacillus  icier oides  discovered  by  him  was  the  specific  agent  of  the 
disease.  Maj.  Reed  in  association  with  Dr.  Carroll  had,  however, 
already  demonstrated  that  this  bacillus  was  one  widely  disseminated 
in  the  United  States,  and  bore  no  special  relation  to  yellow  fever. 

In  June,  July,  and  August,  1900,  the  commission  gave  their  entire 
attention  to  the  bacteriological  study  of  the  blood  of  yellow-fever 
patients  and  the  post-mortem  examinations  of  the  organs  of  those 
dying  with  the  disease.  In  24  cases  where  the  blood  was  repeatedly 
examined,  as  well  as  in  11  carefully  studied  autopsies,  Bacillus 
icteroides  was  not  discovered,  nor  was  there  any  indication  of  the 
presence  in  the  blood  of  a  specific  cause  of  the  disease. 

Application  was  made  to  Gen.  Leonard  Wood,  the  military  governor 
of  Cuba,  for  permission  to  conduct  experiments  on  nonimmune 
persons,  and  a  liberal  sum  of  money  requested  for  the  purpose  of 
rewarding  volunteers  who  would  submit  themselves  to  experiment. 

It  was  indeed  fortunate  that  the  military  governor  of  Cuba  was  a 
man  who  by  his  breadth  of  mind  and  special  scientific  training  could 
readily  appreciate  the  arguments  of  Maj.  Reed  as  to  the  value  of  the 
proposed  work. 


10  YHLLOW      --KVLK. 

Money  and  full  authority  to  proceed  were  promptly  granted,  and  to 
the  everlasting  L-  toe  American  soldier,  volunteers  from  the 

Army  offered  themselves  for  experiment  in  plenty  and  with  the  utmost 
fearlessness. 

Before  the  arrangements  were  entirel\  completed.  I>r.  Carroll,  a 
member  of  thecomm  Slowed  himself  to  be  bitten  bv  a  mosquito 

that  12  days  previously  had  filled  it-elf  with  the  blood  ofayellow- 

:•  patient,      He  -utleivd   from   a    \  er\      <  k.   and    In-  was 

the  first  expenn  .-.      I  >r.  La/car  al-o  experiincnied  on  him-elf 

at  the  same  time,  but  was  not  infected.     Some  days  later,  while  in 
the  yellow-fever  ward,   he  was  bitten  by   a   mosquito  and   noted   the 
•  •quired  the  disease  in  its  most  terrible  form  and 
died  a  martyr  to  -nence  and  a  true  hen.. 

No  other  fatality  occurred  among  the  brave  men  who.  in  the  cour-e 
of  the  experiments,  willingly  exposed  themselves  to  the  infection  of 
ireaded  di-ease. 

A  camp  was  especially  constructed  for  the  experiments  about  1 
miles  from  Habana,  christened  Camp  La/ear  in  honor  of  the  dead 
comrade.  The  inmate-  of  the  camp  were  put  into  mo-t  ri^id  quar- 
antine and  ample  time  was  allowed  to  eliminate  any  possibility  of 
the  disease  being  brought  in  from  Habana. 

The  personnel  consisted  of  three  nurses  and  nine  noniminnnes.  all 
in  the  military  service,  and  included  two  physicians. 

From   time   to   time   Spanish   immigrant >.    newly    arrived, 
brought  in  directly  from  tne  immigrant  station:  a  pW-on  not  ki 
to  be  immune  was  not  allowed  to  leave  camp,  or  if  he  did  was  for- 
bidden to  return. 

The  most  complete  record  was  kept  of  the  health  of  every  man  to 
be  experimented  upon,  thus  eliminating  the  possibility  of  any  other 
disease  than  yellow  fever  complicating  the  case. 

The  mosquitoes  used  were  specially  bred  from  the  eggs  and  kept 
hi  a  building  screened  by  wire  netting.  When  an  in  nted 

for  an  experiment  it  was  taken  into  a  yellow  fever  hospital  and 
allowed  to  fill  it-elf  with  the  blood  of  a  patient;  afterwards  at  varying 
intervals  from  the  time  of  this  meal  of  blood  it  was  purposely  applied 
to  nonimmunes  in  camp. 

In  December,5  cases  of  the  disease  were  developed  as  the  re-nl 
such  applications;  in  January,  3,  and  in  February.  J.  making  in  all 
10,  exclusive  of  the  cases  of  Drs.  Carroll  and  La/ear.      Immediately 
upon  the  appearance  of  the  first  recognized  symptoms  <>f  the  disease, 
in  any  one  of  these  experimental  cases,  the  patient  was  taken  fn>m 
Camp  Lazear  to  a  vellow-f  ever  hospital,  1  miledi-iant.     I 
in  camp  was  rigidly  protected  from  accidental  mosquit •  and 

not  in  a  single  instance  did  yellow  fever  develop  in  the  camp 
at  the  will  of  the  experimenters. 

The  experiments  were  conducted  at  a  season  when  there  was  the 
least  chance  of  naturally  acquiring  the  disease,  and  the  mosquitoes 
used  were  kept  active  by*  maintaining  them  at  a  summer  temperature. 

A  completely  mosquito-proof  building  was  divided  into  two  com- 
partments by  a  wire-screen  partition;  infected  insects  \\eie  liberated 
on  one  side  only.     A  brave  nonimmune  entered  and  remained 
enough  to  allow  himself  to  be  bitten  several  times.     He  was  attacked 

I  yellow  fever,  while  two  susceptible  men  in  the  other  ei.nipartment 
not  acquire  the  disease,  ulthou-h  deeping  there  13  nights.     This 


YELLOW  PEVEK.  11 

demonstrates  in  the  simplest  and  most  certain  manner  that  the  infeo- 
tiousness  of  the  building  was  due  only  to  the  presence  of  the  insects. 

Every  attempt  was  made  to  infect  individuals  by  means  of  bedding, 
clothes,  and  other  articles  that  had  been  used  and  soiled  by  patients 
suffering  with  virulent  yellow  fever. 

Volunteers  slept  in  the  room  with  and  handled  the  most  filthy 
articles  for  20  nights,  but  not  a  symptom  of  yellow  fever  was  noted 
among  them,  nor  was  their  health  in  the  slightest  degree  affected. 
Nevertheless  they  were  not  immune  to  the  disease,  for  some  of  them 
were  afterwards  purposely  infected  by  mosquito  bites.  This  experi- 
ment indicates  at  once  the  uselessness  of  destroying  valuable  property 
for  fear  of  infection.  Had  the  people  of  the  United  States  known 
this  one  fact  100  hundred  years  ago,  an  enormous  amount  of  money 
would  have  been  saved  to  householders. 

Besides  the  experimental  cases  caused  by  mosquito  bite,  four  non- 
immunes  were  infected  by  injecting  blood  drawn  directly  from  the 
veins  of  yellow-fever  patients  in  the  first  two  days  of  the  disease, 
thus  demonstrating  the  presence  of  an  infectious  agent  in  the  blood  at 
this  early  period  of  the  attack. 

Even  the  blood  serum  of  a  patient,  passed  through  a  bacteria-proof 
filter,  was  found  to  be  capable  of  causing  yellow  fever  in  another 
person. 

The  details  of  the  experiments  are  most  interesting,  but  it  must 
here  suffice  to  briefly  sum  up  the  principal  conclusions  of  this  admirable 
board  of  investigators  of  which  Reed  was  the  master  mind: 

1.  The  specific  agent  in  the  causation  of  yellow  fever  exists  in  the 
blood  of  a  patient  for  the  first  three  days  of  his  attack,  after  which 
time  he  ceases  to  be  a  menace  to  the  health  of  others. 

2.  A  mosquito  of  a  single  species,  Sjejg^jnjYJafa^cjat^,  ingesting  the 
blood  of  a  patient  during  this  infectiveperioaTs  powerless  to  convey 
the  disease  to  another  person  by  its  bite  until  about  12  days  have 
elapsed,  but  can  do  so  thereafter  for  an  indefinite  period,  probably 
during  the  remainder  of  its  life. 

3.  The  disease  can  not  in  nature  be  spread  in  any  other  way  than 
by  the  bite  of  the  previously  infected  Stegomyia.     Articles  used  and 
soiled  by  patients  do  not  carry  infection. 

These  conclusions  pointed  so  clearly  to  the  practical  method '  of 
exterminating  the  disease  that  they  were  at  once  accepted  by  the 
sanitary  authorities  in  Cuba,  and  put  to  the  test  in  Habana,  where 
for  nearly  a  century  and  a  half,  by  actual  record,  the  disease  had 
never  failed  to  appear  annually. 

In  February,  1901,  the  chief  sanitary  officer  in  Habana,  Maj.  W.  C. 
Gorgas,  Medical  Department,  United  States  Army,  instituted  meas- 
ures to  eradicate  the  disease,  based  entirely  on  the  conclusions  of  the 
commission.  Cases  of  yellow  fever  were  required  to  be  reported  as 
promptly  as  possible,  the  patient  was  at  first  rigidly  isolated,  and 
immediately  upon  the  report  a  force  of  men  from  the  sanitary  depart- 
ment visited  the  house.  All  the  rooms  of  the  building  and  or  the 
neighboring  houses  were  sealed  and  fumigated  to  destroy  the  mos- 
quitoes present.  Window  and  door  screens  were  put  up,  and  after 
the  death  or  recovery  of  the  patient,  his  room  was  fumigated  and 
every  mosquito  destroyed.  A  war  of  extermination  was  also  waged 
against  mosquitoes  in  general,  and  an  energetic  effort  was  made  to 
diminish  the  number  bred  by  draining  standing  water,  screening  tanks 


12  YELLOW  FEVBB. 

and  vessels,  using  petroleum  on  water  that  could  not  he  drained,  anil 
in  the  most  systematic  manner  destroying  the  breeding  place-  of  the 
insects. 

When  the  warm  season  returned  a  few  cases  oc< -ured.  hut  1>\  Sep- 
tember, 1901 ,  the  last  case  of  yellow  fever  originated  in  Habana.  since 
which  time  tin  i -it  v  has  been  entirely  exempt  from  the  terrihle  dis- 
ease, that  had  there  kept  stronghold  for  150  years.  Cases  are  now 
admitted  into  Haba  an  ports,  but  are  mated  under 

screens  with  perfect  impunity,  in  the  ordinary  city  hospitals.     The 
.•ide  against  the  insects  also  caused  a  very  large  decrease  in  mala- 
rial fevers. 

The  destruction  of  the  most   fatal  epidemic  disease  of  the  Western 
Hemisphere,  in  its  favorite   home   city    is   hut    the   he-inning  of   the 
benefit  to  mankind  that  may  he  expected  to  follow  the  work  of  ! 
and  his  associates.     There  can  be  no  manner  of  d <m ht  should  Mexico, 
Brazil,  and  the  Central  American   Republics,  where  the  disease  still 
exists,  follow  strictly  the  example  set  by  Habana,  that  yellow  fever 
will  become  extinct    and   the   I  nited   States  forever  freed   fn»m   the 
scourge  that  has  in  the  past  slain   thousands  of  our  citi, 
caused  the  loss  of  untold  treasure. 

More  recent  investigations  into  the  cau-e  and  spread  of  yellow 
fever  have  only  succeeded  in  verifying  the  work  of  Keed  and  his 
commission  in  every  particular  and  in  adding  very  little  t«»  «.ur  kno\\  I- 
edge  of  the  disease. 

Later  researches  by  Guiteras  in  Habana,  by  the  Puhlic  I  lealt  h  and 
Marine-Hospital  Service  in  VeraCruz,  and  lastly  by  a  delegation  from 
the  Pasteur  Institute  of  Paris  in  Rio  de  Janeiro,  all  confirm  in  the 
most  convincing  manner  both  the  accuracy  and  comprehensive 
of  the  conclusions  of  the  American  commission.    It  h  well 

said  that  Reed's  experiments  "will  always  remain  as  models  in  the 
annals  of  scientific  research,  both  for  the  exactness  with  which  they 
were  adapted  to  the  points  to  be  proved,  and  the  precautions  t 
that  no  experiment  should  be  vitiated  by  failure  t<>  exclude  all  possihle 
sources  of  error." 

Appreciation  of  Reed's  work  was  instant  in  the  scientific  world. 
Honorary  degrees  from  Harvard  University  and  the  Tim 
Michigan  were  conferred  upon  him,  learned  societies  and  di-i  mini 
men  delighted  to  honor  him,  and  after  his  death  Congress  voted  a 
special  pension  to  his  widow. 

To  the  United  States  the  value  of  his  services  can  not  he  estimated. 
Ninety  times  has  yellow  fever  invaded  the  country,  carryii 
and  destruction,  leaving  poverty  and  grief. 

NewOrlean-.  Memphis,  Charleston,  Galve-t on,  Portsmouth.  Balti- 
more, Philadelphia,  New  York,  and  many  -mailer  towns  have  been 
swept  by  the  disease. 

The  epidemic  of  1853  cost  New  Orleans  8,000  lives,  that  of  1793 
wiped  out  10  per  cent  of  Philadelphia's  population. 

The  financial  loss  to  the  Ui  he  one  epidemic  of  1878 

was  estimated  as  amounting  to  $15,335,000,  but  suffering,   panic, 
fear,  and  the  tears  of  widows  and  orphans  can  never  be  estimated. 
however,   if  yellow   fever  should   again  cross   our  southern 
border,  there  need  be  no  disturbance  of  commerce  or  loss  of  prop- 
in  the  slightest  degree  comparaMe  with  that   which  epidemics 
in  the  past  have  caused. 


YELLOW  FEVER.  13 

The  death  of  Maj.  Reed  took  place  November  23,  1902,  in  Wash- 
ington, from  appendicitis.  It  is  gratifying  to  think  that,  although 
his  country  and  the  scientific  world  were  deprived  of  one  from 
whose  future  services  more  benefit  to  humanity  might  reasonably  be 
expected,  nevertheless  he  was  privileged  before  his  life's  close  to 
know  that  his  discovery  had  been  tested,  and  that  a  great  city  was 
freed  from  her  ancient  foe,  to  know  that  his  conscientious  work  had 
contributed  immeasurably  toward  the  future  prospects  of  an  infant 
Republic,  and  even  more  to  the  welfare  of  his  own  beloved  country, 
whose  flag  he  had  served  so  faithfully. 

In  the  national  capital  and  in  the  great  cities  of  the  United 
States,  there  are  stately  monuments  to  the  country's  great  ones. 
Statues  of  warriors,  statesmen,  and  patriots  stand  as  silent  wit- 
nesses of  a  people's  gratitude.  Is  there  not  room  for  the  effigy  of 
Walter  Reed,  who  so  clearly  pointed  out  to  his  fellow  man  the  way 
to  conquer  America's  worst  plague  ? 


CHAPTER  2. 

SKETCH  OF  THE  LIFE  OF  MAJ.  WALTER  REED,  SURGEON, 
UNITED  STATES  ARMY. 

By  JEFFERSON  R.  KBAN,  Major,  Medical  Corps,  United  States  Amu. 

Walter  Reed,  M.  D.,  LL.  D.,  M.  A.,  major  and  surgeon  .  I  'nited 
States  Army,  was  born  September  13,  1851,  in  Gloucester  ('..unty. 
Va.,  and  was  the  son  of  tne  Rev.  Lemuel  Sutton  Reed,  a  leading 
Methodist  divine  of  that  State.  His  ancestors  came  from  North 
Carolina,  having  been  amonp  the  earliest  settlers  of  that  colony.  I  Ie 
gave  early  evidence  <>f  the  intellectual  brilliancy  and  earnestness  of 
purpose  which  distinguished  him  in  later  years,  and  graduated  in 
medicine  at  the  University  of  Virginia  in  1869.  11  <  i  <  ><  >k 

the  degree  of  M.  D.  in  Bellevue  Medical  College,  New  York  City.     He 
served  as  house  surgeon  in  the  Brooklyn  City  Hospital  and  tin-  city 
hospital  on  Blackwells  Island  ,  and  before  the  age  <  »  f  '2  1  was  appointed 
a  district  physician  in  New  York  City.     He  was  also  appointed  one 
of  the  five  inspectors  of  the  board  of  health  of  the  city  of  Brooklyn 
at  the  age  of  22.     In  1875  he  entered  the  Medical  Corps  of  the  Army. 
and  for  18  years  thereafter  performed  the  customary  dm. 
medical  officer  at  various  posts  in  different  parts  of  the  United  > 
and  in  the  field.     His  military  service  included  1  f>  changes  of  station. 
with  4  years  in  Arizona,  5  in  the  Department  of  the  IMatte.  J  in  the 
Department  of  Dakota,  3  in  the  South,  and  3  years  in  the  East.     He 
was  promoted  full  surgeon  with  the  rank  of  major  December  4,  1 
and  at  the  time  of  his  death  was  first  on  the  list  of  majors  in  the 
Medical  Department  of  the  Army.     In  the  fall  of  1890  he  was  a^iimed 
to  duty  as  attending  surgeon  in  Baltimore,  Md..  which  M  he 

held  for  a  year.     He  promptly  embraced  this  opportunity  to  1 
special  studies  in  bacteriology  and  pathology,  and  s<  M.M  won  t 
tion  and  esteem  of  Prof.  Wmiam  II.  Welch. 


This  was  the  he^mnin^ 
of  a  close  friendship  with  that  distinguished  scientist  \\hich  lasted 
until  the  untimely  death  of  Maj.  Reed,  on  November  23,  1" 

In  1893  Maj.  Keed  was  placed  on  duty  in  Washington  as  <  nrator 
of  the  Army  Medical  Museum  and  appointed  the  professor  of  bacte- 
riology of  the  newly  organized  Army  Mcdieal  School. 

In  the  10  years  subsequent  to  this  date,  in  the  intervals  of  his 
routine  duties  and  others  which  came  to  him  as  a  medical  officer,  such 
as  member  of  examining  hoards,  teaching,  investigation  <>f  numerous 
sanitary  questions,  and  making  sanitary  inspections,  he  was  ahlc.  l>\ 
immense  industry,  to  obtain  a  position  ID  the  scientific  worl.i 
comes  to  few  of  those  who  are  able  to  devote  a  lifetime  exclusive^  to 
such  pursuits. 

Of  the  numerous  monographs  which  show  his  scientific  work  during 
this  time,  all  are  credit  a  hie:  nor  do  any  show  marks  of  can  •!••-  -n.-~-  or 
haste,  in  spite  of  the  limited  time  which  he  had  at  Ids  disposal. 
14 


YELLOW   FEVER.  15 

In  1898,  when  typhoid  fever  prevailed  so  extensively  in  the  camps 
of  the  Volunteer  Armies  of  the  United  States,  Maj.  Reed  was  put  at  f/ 
the  head  of  a  commission — Dr.  Victor  C.  Vaughan,  of  the  University 
of  Michigan,  and  Dr.  E.  O.  Shakespeare,  of  Philadelphia,  being  the 
other  members — to  study  the  causation  and  methods  of  spread  of  that 
disease.  This  investigation,  which  covered  a  period  of  more  than  a 
year,  was  remarkable  for  the  patience  and  skill  with  which  a  vast 
number  of  details  were  assembled,  and  studied,  and  it  marks  a  great 
advance  in  our  knowledge  of  this  widespread  disease.  Among  the 
points  of  great  value  brought  out  were  the  importance  of  the  common 
fly  as  a  carrier  of  infection  in  camps,  and  the  frequency  with  which 
the  contagion  of  typhoid  fever  is  in  camp  life  spread  from  man  to 
man  by  immediate  contact  with  each  other  or  with  bedding,  tents, 
and  implements  which  have  become  infected.  Strangely  enough,  this 
report  nas  never  been  published  in  full,  but  only  an  abstract  of  it 
containing  some  240  pages,  and,  on  account  of  the  failure  to  publish 
and  disseminate  the  lull  report,  its  conclusions  are  but  little  known 
abroad  or  among  the  members  of  the  medical  profession  in  this 
country.  Many  of  the  facts  contained  in  it  were  rediscovered  by 
the  English  during  the  Boer  War,  and  it  is  probable  that  its  prompt 
publication  and  dissemination  would  have  saved  many  thousand  lives 
during  that  war. 

The  first  work  by  Maj.  Reed  bearing  on  the  causation  of  yellow 
fever  was  in  1899-1900,  when  he  overthrew  the  claim  of  the  dis- 
tinguished bacteriologist,  Sanarelli,  to  have  discovered  the  bacillus  of 
yellow  fever,  by  his  demonstration  that  the  Bacillus  icteroides  (Sana- 
relli) was  an  organism  widely  disseminated  in  this  country  and  having 
no  causative  relation  to  that  disease.  He  began  the  special  work  with 
which  his  name  will  always  be  inseparably  associated  as  one  of  the  ben- 
efactors of  mankind  in  June,  1900,  when  he  went  to  Cuba  as  presi- 
dent of  a  commission  to  study  the  infectious  diseases  of  Cuba,  with 
special  reference  to  yellow  fever.  The  other  members  of  this  commis- 
sion were  Acting  Asst.  Surgs.  James  Carroll,  Jesse  W.  Lazear,  and 
A.  Agramonte.  The  time  was  most  opportune  for  such  investigation, 
as  the  disease  was  at  that  time  prevalent  both  in  Habana  and  in  the 
little  town  of  Quemados,  near  the  camp  of  the  American  troops,  and 
it  was  plainly  evident  that  the  energetic  measures  of  the  American 
military  government  to  clean  up  the  towns,  disinfect,  and  enforce 
other  sanitary  measures  were  without  effect  in  preventing  the  spread 
of  this  particular  disease.  Maj.  Reed  became  convinced  that  proper 
sanitation  was  not  all  that  was  needed,  and  that  some  other  agent  than 
unclean  conditions  was  responsible  for  the  spread  of  the  disease. 

The  transmission  of  malaria  by  a  certain  species  of  mosquito  had 
been  recently  demonstrated  by  the  English  military  surgeon,  Ronald 
Ross.  The  theory  had  also  been  advanced  both  by  a  Mobile  physician 
and  by  Dr.  Finlay,  of  Habana,  that  a  mosquito  was  the  agent  for  the 
transmission  of  yellow  fever;  but  these  theories,  being  unsupported 
by  scientific  demonstration,  received  no  more  attention  than  the  vast 
number  of  others  which  had  been  at  one  time  or  another  advanced 
with  regard  to  this  mysterious  and  deadly  disease. 

Dr.  Reed's  attention  was  attracted  by  a  paper  on  the  spread  of  yellow 
fever  in  Ormond,  Miss.,  by  Dr.  H.  R.  Carter,  of  the  Marine-Hospital 
Service,  in  which  it  was  shown  that  although  the  period  of  incuba- 
tion of  the  disease  was  5  days,  15  or  20  elapsed  before  a  house 


16 

became  infected  aft-  i<-k  with  yellow  fever  was  carried  into 

it.  :red  that  thoditfere!  B6D  tin1  timoof  incuhat ion  and 

the  time  required  to  infect  a  building  was  due  to  the  fact  that  the 
infective  airent  pas-.  -o  of  d«  'it  in  the  body  of 

some  biting  insect  as  an  intermediate  host,  and  heat  once  determined 

iments  along  thai  lino.     It  wasevident  to  his  mind 

that  the  so! ul ion  of  this  question,  which  meant  SO  much  for  the  human 

'erinined  without  cxperimci 

human  hoin^s.  and  ho  •  tl.o  military  ^o\ ei : 

Cuba,  to  a>k  permission  to  conduct  such  experiments,  and  I 

•o  liberally  reward  voh:;  irho  should  suhmit  them- 

selves for  ON  (  W        I   promptly  granted   both,  with  a 

ready  a;  iportance  of  the  matter  ami  tho  for 

\\hich  will  entitle  him  to  no  small  measu 
*  the  f  this  di-cox 

/      Meanwhile,  during  n  temporary  ab-eneo  of  Dr.  Koed  in  the  Initrd 
/  States,  his  assistants,  Dr.  J  .roll  and   Dr.  Jr»e  \V.   L.-i, 

/   who  had  offored  theiii-cl\ cs  as  the  first  volunt*  . 
demonstrated  that  moMpiitnes  wmild  • 
Dr.  Carroll,  who  was  the  first  oxporimon: 

:.-k,  but  i  d.      Dr.  La/,  IK'!  infected  at  1  •.  due 

to  the  fact  that  the  conditions  >  v  to  the  tran-mi  —  i<m  of  the 

disease  by  the  moxpiito  were  not  yet    understood,  but    be  was  bit  ton 
while  working  in  the  yellow-fever'  ward  s(»me\\hat   later,  and  died  a 

martyr  of  science,  working  in  behalf  of  humanity.    Thi-  only 

fatality  which  occurred  in  these  experiments.     The  fourth  inonil 

mission,  Dr.  Airramnnto,  did  not  participate  in  the  moMjiiiio 
work  of  the  commission  until  a  later  date,  nor  did  he  share  their  dan- 
gers, as  he  was  a  Cuban  and  immune. 

Immediately  upon  Dr.  Heed's  return  arrangements  \\cro  made.  \\  ith 
assistance  of  the  military  governor,  asstato«l  above,  for  a  series  of 
experiments  which,  by  precision  of  detail  and   ri-idnoss  of  control, 
would  admit  of  no  uncertainity  of  interpretation  and  would  bo  a 

non-tration,  carrying  conviction  to  every  scientific  and 
unprejudiced  mind.  These  experiments  will,  as  stated  by  Prof. 
William  II.  Welch,  always  remain  as  models  in  thoannal  ntific 

research,  both  for  the  exactness  with  which  they  were  adapted  to  the 
points  to  be  proved  and  the  precautions  taken  that  no  experiment 
should  be  vitiated  by  failure  to  exclude  all  po>sihlo  sources  of  «• 
They  were  conducted  in  a  camp  especially  constructed  for  the  pur- 
pose, about  4  miles  from  Habana,  and  appropriately  named  "Camp 
Lazear.y     The  history  of  the  work  is  best  .iriven  in'  Dr.   K<  • 
words,  in  an  article  published  in  the  Journal  of  Hygiene,  Cambn 
England. 


? 

(/ 


CHAPTER  3. 

EXPERIMENTS  CONDUCTED  FOB  THE  PURPOSE  OF  COPING  WITH     - 

YELLOW  FEVER. 

[Senate  Document  No.  10,  Fifty-ninth  Congress,  second  session.] 

To  the  Senate  and  House  of  Representatives: 

The  inclosed  papers  are  transmitted  to  the  Congress  in  the  earnest 
hope  that  it  will  take  suitable  action  in  the  matter.  Maj.  Reed's 
part  in  the  experiments  which  resulted  in  teaching  us  how  to  cope 
with  yellow  fever  was  such  as  to  render  mankind  his  debtor,  and  this 
nation  should  in  some  proper  fashion  bear  witness  to  this  fact. 

THEODORE  ROOSEVELT. 
WHITE  HOUSE,  December,  5,  1906. 


[Inclosure  1.] 
[Memorandum  for  the  President,  through  The  Military  Secretary  of  the  Army.| 

WAR  DEPARTMENT, 
OFFICE  OF  THE  SURGEON  GENERAL, 

Washington,  August  30,  1906. 

The  persons  taking  an  important  part  in  the  investigations  in 
Cuba,  which  resulted  in  the  demonstration  of  the  fact  that  yellow 
fever  is  transmitted  by  a  species  of  mosquito,  were  three  members  of  ^ 
the  board  appointed  to  investigate  epidemic  diseases  in  Cuba- 
Walter  Reed,  James  Carroll,  and  Jesse  W.  Lazear — and  the  indi- 
viduals who  submitted  themselves  for  experimentation  by  receiving 
the  bites  of  infected  mosquitoes,  by  receiving  injections  of  blood  from 
yellow-fever  patients,  and  by  sleeping  in  bedding  which  had  been 
used  by  yellow-fever  patients. 

When  the  Yellow  Fever  Commission,  composed  of  Walter  Reed, 
James  Carroll,  Jesse  W.  Lazear,  and  A.  Agramonte,  assembled  in 
Habana  they  had  no  thought  of  investigating  the  connection  of  the 
mosquito  with  the  spread  of  yellow  fever.  This  idea  came  to  Dr. 
Reed  after  the  board  had  demonstrated  that  the  claim  of  Sanarelli, 
concurred  in  by  Wasdin  and  Geddins,  that  the  Bacillus  icteroides 
was  the  cause  of  yellow  fever  was  without  foundation.  Dr.  Reed 
then  determined  to  investigate  the  theory  of  Dr.  Carlos  Finlay, 
that  the  mosquito  was  instrumental  in  conveying  yellow  fever,  which 
theory  Finlay  had  failed  to  demonstrate,  and  which  was  not  then 
accepted  by  scientific  men.  This  determination  was  reached  for  the 
reasons  which  are  well  stated  in  Dr.  Kelly's  biography,  and  was 
original  with  Reed,  not  being  suggested  to  him  by  anyone.  The 
final  determination  to  investigate  the  mosquito  theory  was  arrived  at 
during  an  informal  meeting  of  the  board  (Dr.  Agramonte  being 
absent)  at  Columbia  Barracks  on  the  evening  before  Dr.  Reed's 

79965°— S.  Doc.  822,  61-3 2  17 


18 

departure  for  the  United  States,  early  in  August,  l'.»0l.  It 
agreed  by  these  members  of  the  board  that  in  making  the  expcri- 
ments  on  human  beings,  by  which  alone  the  demonstration  could -ho 
made,  that  they  should  submit  themselves  a^  subject-  for  experimen- 
tation. To  Dr.  Lazear,  who  was  familiar  with  mosquito  \\ork. 
assigned  t lie  duty  of  breeding  and  infect  in-_:  the  moxjuitor-.  while 
Dr.  Carroll  was  to  continue  the  bacteriological  work  on  which  the 
board  had  been  engaged. 

On  August  2,  1900,  before  the  mosquitoes  were  ready   for  the 
/experiment,  Dr.  Reed  was  called  back  to  Washington  to  prepare 
/  for  publication  the  abstract  of  the  report  of  the  hoard  appointed  "m 
I  1898  to  investigate  the  spread  of  typhoid   fever  in   tie   volunteer 
'  camps  in  the  United  States,  of  which  board  lie  was  president.     This 
vast  work,  of  which  the  full  report  was  pu hi ished  by  special  authority 
of  Congress  about  a  year  after  Dr.  IJeed's  d<>ath,  by  the  onl\ 
viving  meml)er  of  the"   hoard.  Prof.   Victor  ('.  Vaughan,  of   the  Tni 
versify  of  Michigan,  was  one  of  the  most  valuable  contributio 
science  which  has  been  made  by  the  Surgeon  General's  (  Mlice.     The 
work  of  preparation  of  the  abstract  report    had  been  brought   t<»  a 
standstill  by  the  sudden  death  of  the  third  member  of  the  b« 
Dr.  Kduard  O.  Shakespeare,  of  Philadelphia,  and  Dr.  Recd'^  presence 
at  this  time  was  essential  for  its  completion. 

During  Dr.  Reed's  absence  the  inoculations  by  means  of  the 
mosquito  were  begun.  On  August  11,  Dr.  Lazear  made  the  lirst 
experiment,  but  nine  distinct  inoculations  on  per>«»n-.  iix-ludini:  him- 
selr  and  Acting  Asst.  Surg.  A.  S.  Pinto,  were  unsuccessful.  We  know 
now  that  these  failures  were  due  to  two  facts — first,  that  patients 
after  the  third  day  of  the  disease  can  not  convey  the  infection  to  the 
mosquito,  and  second,  that  after  having  bitten  a  yellow-fever  case  the 
mosquito  can  not  transmit  the  disease  until  after  an  interval 
least  12  days.  On  August  27  one  mosquito  was  applied  to  Dr. 
Carroll,  one  which  happened  to  fulfill  both  of  these  conditions,  The 
result  was  a  very  severe  attack  of  yellow  fever,  in  which  for  a  time 
his  life  hung  in  the  balance.  This  was  thus  trie  fiist  expcrii: 
case.  The  fever  developed  on  the  31st  of  August,  on  which  day  Dr. 
Lazear  applied  the  same  mosquito  which  bit  Dr.  Carroll  with  three 
others  to  another  person.  This  man  came  down  with  a  mild  but 
well-marked  case. 

On  September  13  Dr.  Lazear,  while  on  a  visit  to  Las  Am 
Hospital    (for   the   purpose  of  collecting   blood    from    \<ll<>\\ 
patients  for  study)  was  bitten  by  a  mosquito  of  undetermined  sp< 
which  he  deliberately  allowed  to  remain  on  the  back  of  his  hand  until 
it  had  satisfied  its  hunger.     Five  days  thereafter   he   came  do\sn. 
without  ot her  exposure,  with  yellow  fever,  which  p  !  steadily 

to  a  fatal  termination.     These  three  cases  established  in  Keed's  mind 
the  proof  of  the  mosquito  theory  and  made  it,  in  the  opinion  of  his 
friends,  an  unnecessary  and  foolish  ri>k  for  him.  at  his  ap-.  to  submit 
himself  to  inoculation.     These  cases,  with  his  deduction-;  t1 
were  reported  by  the  board  in  a  paper  called  "The  <>tio|o/\  of  \«-ll«»w 

fever — A  preliminary  note."  read   before  the  American   Public   1! 

Association  at  Buffalo,  \.  V.,  October  22-26,  1900.  He  then 
immediately  returned  to  Cuba  to  undertake  a  second  and  mo  in- 
elaborate series  of  experiments  which  were  made  possible  by  the, 
promise  made  to  him  by  Gen.  Wood  on  October  12,  when  told  by 


YELLOW   FEVER.  19 

Reed  of  the  experiments  already  made,  to  assist  him  with  whatever 
money  was  necessary.  This,  the  second  series  of  experiments,  began 
November  20  at  an  experimental  camp  near  Quemados,  called  Camp 
Lazear,  and  embraced  14  cases,  of  which  the  last  was  taken  sick 
February  10,  1901.  Of  these,  10  were  mosquito  infections  and  4 
were  infected  by  injection  of  the  blood  of  yellow-fever  patients.  All 
of  these  cases  recovered. 

A  third  series  of  6  cases  was  produced  by  Dr.  James  Carroll 
the  next  fall  to  settle  certain  undetermined  facts  as  regards  the 
etiology  of  the  disease.  The  first  of  these  cases  came  down  with 
the  fever  September  19,  1901,  and  the  last  on  October  23,  1901.  Of 
these  cases  2  were  caused  by  mosquitoes  and  4  by  blood  injec- 
tions. None  of  them  resulted  fatally.  The  highly  dangerous  char- 
acter of  these  experiments  and  the  good  fortune  of  the  board  in  its 
second  and  third  series  of  cases  is  shown  by  the  fact  that  Dr.  Guiteras, 
of  Habana,  in  a  series  of  7  cases  inoculated  in  Habana  lost  3,  bring- 
ing his  experiments  abruptly  to  an  end. 

No  enumeration  of  unsuccessful  cases — namely,  those  which  failed 
to  cause  the  disease — has  been  made,  although  it  is  obvious  that  the 
persons  undergoing  such  experiments  exhibited  as  much  courage  as 
those  in  which  the  disease  was  transmitted,  This  is  especially  true 
of  the  cases  occurring  after  the  severe  case  of  Dr.  Carroll  and  the 
fatal  case  of  Dr.  Lazear.  Certain  ones  of  these  unsuccessful  cases 
deserve  special  mention,  being  those  made  with  infected  bedding 
at  Camp  Lazear.  In  a  specially  constructed  house  at  that  camp, 
which  was  intentionally  ill  ventilated  and  kept  continually  at  a 
summer  temperature,  was  placed  a  large  quantity  of  bedding  taken 
from  the  beds  of  patients  sick  with  yellow  fever  in  Habana  and 
soiled  with  their  discharges.  In  this  house  Acting  Asst.  Surg.  R.  P. 
Cook  and  two  privates  of  the  Hospital  Corps  slept  continuously 
from  November  30  to  December  19.  Each  morning  they  packed  the 
various  soiled  articles  of  bedding  in  boxes  and  unpacked  them  at 
night,  when  they  were  used  to  sleep  on. 

From  December  21,  1900,  to  January  10,  1901,  the  building  was 
again  occupied  by  two  nonimmune  Americans  under  the  same  cir- 
cumstances, except  that  an  additional  stock  of  very  much  fouled 
bedding  and  clothing  had  been  added  to  the  collection,  and  these 
men  slept  every  night  in  the  very  garments  worn  by  yellow-fever 
patients  throughout  their  entire  attacks,  besides  making  use  of  their 
much  soiled  pillow  slips,  sheets,  and  blankets.  A  third  couple  of 
Hospital  Corps  men  succeeded  these  for  an  equal  length  of  time. 
None  of  these  seven  individuals  contracted  yellow  fever,  but  the 
courage  and  fortitude  shown  by  them  certainly  equal  that  of  those 
who  submitted  to  the  bites  of  the  mosquitoes,  it  being  borne  in  mind 
that  belief  in  the  transmission  of  yellow  fever  by  infected  bedding 
and  clothing  was  at  that  time  practically  universal,  whereas  the 
mosquito  theory  had  still  very  few  converts. 

After  this  brief  history  of  this  great  discovery  a  statement  of  the 
part  borne  by  each  of  the  more  important  participators  in  it  is 
necessary  to  a  determination  of  the  reward  which  would  be  appro- 
priate to  each. 

Maj.  Walter  Reed,  surgeon,  United  States  Army,  president  of  the 
commission  to  investigate  and  study  the  epidemic  diseases  in  Cuba, 
died  in  Washington  from  appendicitis,  November  23,  1902,  at  the 


20  YKI.I.oW     KKVKK. 

age  of  ~>1.     At  the  time  of  his  drat  11  the  Secretary  of  War  had  said  in 
his  report,  which  was  then  in  press  but  not  \  ei  -/IN  en  <>ut : 

The  brilliant  character  of  this  ncimtilic  :i<hi«-\vni<-ni.  ii-  mrstimai.l.-  \alu,>  t,. 
mankind,  the  savinp  of  thousands  of  lives,  and  thod.  li  h.  Atlanticseacoaat 

constant  apprehon-  .md  special  recognition  from  the  Government  «»f 

the  United  States. 

lleed  is  the  ranking  major  in  the  Medical  Department,  and  within  a  few  months 
will,  by  operation  of  law,  booum-  II.-UI.-M. mi  .  -l-n.-l.  I  a*k  that  the  President  I... 
authorized  to  appoint  him  Assistant  Surgeon  <i. -ii.-r.il  with  th«-  rank  ol 

Gen.  Leonard  W.MM!  said  of  him  in  an  address  delivered  at  a 
memorial  meeting  of  scientific  men  in  Wa^hinirton,  D.  C.,  shortly 
after  his  death: 

I  know  of  no  other  man  on  this  side  of  the  world  wh<>  has  done  BO  mm  h  i"»r  humanity 
as  Dr.  Reed.  His  diflCO very  r  !;v«-s  annualh  thai 

lost  in  the  Cuban  war,  and  saves  the  « •••mnu-n -ial  ini« n-staof  the  world  agn 
cial  loss  each  year  than  the  cost  of  the  Cuban  war      II.  c -aim-  t..  (  nl.;i 
one-third  of  tn«  f  my  staff  died  of  yellow  fever,  and  we  were  discouraged  at 

thefailure  rto  to  control  the  dteaw. 

In  the  months  when  the  disease  was  ordinarily  worst  the  disease  was  checked 
and  driven  fr<>m  Habana.     That  was  the  firet  time  in  n.-arly  200  year-  ihat  th 
had  been  rid  of  it.     The  value  of  his  discovery  ran  n«t  l« 
who  are  not  familiar  with  the  conditions  of  tropical  countric.-       I  |.-r.  .,n.-r  it  will 
be  possible  for  v<'ll«»w  fever  to  gain  such  headway  that  fjuarantine  wr  m  the 

mouth  of  the  Potomac  to  the  mouth  of  th  mde,     Future  <:.-m -rat i..[. 

appreciate  fully  the  value  of  Dr.  Reed's  services.     His  was  the  or 
and  controlling  mind  in  this  work,  and  the  others  were  assistants  only 

In  a  letter  from  Prof.  Welch  to  the  Secretary  of  War  he  said  : 

Dr.  Reed's  researches  in  yellow  fever  are  by  far  the  most  important  contributions  to 
science  which  have  ever  come  from  any  Army  surgeon.     In  my  judgment  ihey  are 
the  most  valuable  contributions  to  medicine  and  public  hygiene  wnich  ha\« 
been  made  in  this  country  with  the  exception  of  the  discovery  of  anapsthesi 
have  led  and  will  lead  to  the  saving  of  thousands  of  lives.     I  am  in  a  positi< 
that  the  credit  for  the  original  ideas  embodied  in  this  work  \» •! 
Reed. 

Prof.  Welch  was  Dr.  Reed's  teacher  in  bacteriology  and  was  his 
intimate  and  confidential  friend,  with  whom  h<>  consulted  ahotit  the 
details  of  the  work  in  Cuba. 

A  bill  prepared  in  this  office  for  a  pension  for  his  widow,  (><jual  in 
amount  to  his  monthly  pay,  was  passed,  but  the  amount  was  so  cut 
down  that  while  it  keeps  the  wolf  from  the  do«»r  it  does  m»t  pro- 
vide an  adequate  and  comfortable  income.  It  i^  not  probable,  how- 
ever, that  Congress  would  increase  this  pension,  and  an  e!l'«>rt  has 
been  made  to  supplement  it  by  the  raising  of  a  fund  of  SiM.onn  by  the 
Walter  Reed  Memorial  Association,  incorporated  for  this  pm 
in  the  District  of  Columbia.  The  interest  on  this  fund  will  be  ^ivcn 
Mrs.  Reed  during  her  lifetime,  and  the  principal,  after  her  death,  will 
be  devoted  to  some  form  of  memorial.  This  fund  lacks  at  present 
about  $6,000 of  comnlet ion.  The  existence  of  tin  ution,  >hould 

its  hopes  be  attained,  does  not .  however,  absolve  the  nation  from  the 
obligation  of  a  fitting  rer<,Lrnjt ion  for  this  trreat    work,  and   it    is  the 
opinion  <.f  the  undersigned,  which,   it    U   believed,   is  Chared   by    the 
vast  majority  of  physicians   in   the  United   States,    that    < 
should  erect  a  statue  to  Walter  Reed  in  Washington.     The  assist 
of  the  President  in  inducing  Con  •  do  so  is  re<me-ted. 

The  second  member  of  tne  cniun i js-i .MI  wii  Dr.  James  Carrofl,  ;«i 
that  time  acting  assistant  surgeon,  I* nit.  my. 

Dr.  Carroll  is  now  -r,_'  years  old.     Me  entered  the  milhan 
June  9,  1874,  and  served  as  private,  corporal,  sergeuni    and  ho-pit.il 


YELLOW  FEVER.  21 

steward  from  that  date  to  May  21,  1898,  when  he  was  appointed  acting 
assistant  surgeon.  He  was  appointed  first  lieutenant  and  assistant 
surgeon  in  the  Medical  Corps  October  27,  1902,  which  rank  he  still 
holds. 

Dr.  Carroll  was  Dr.  Reed's  truest  assistant  and  coadjutor  from  the 
inception  of  the  work  which  resulted  in  the  discovery  of  the  method 
of  propagation  of  yellow  fever.  As  stated  above,  the  third  series  of 
experiments  were  performed  by  Dr.  Carroll  alone,  Dr.  Reed  having 
been  refused  permission  to  return  to  Cuba  to  complete  his  work. 

Dr.  Carroll  was  the  first  experimental  case  of  yellow  fever,  and  he 
suffered  a  very  severe  attack,  to  which  he  attributes  a  heart  trouble 
from  which  he  now  suffers.  At  the  time  of  undergoing  this  experi- 
ment he  was  46  years  old,  an  age  at  which  the  risk  from  this  disease 
is  very  great,  as  its  mortality  rapidly  increases  with  age  of  patient. 
He  had  at  that  time  a  wife  and  five  children  who  had  no  other  means 
of  support  except  his  pay  as  an  acting  assistant  surgeon. 

It  is  recommended  that  Congress  be  asked  to  pass  a  special  act  pro- 
moting Dr.  Carroll,  on  account  of  his  services  in  connection  with  this 
discovery  and  the  courage  shown  by  him  insubjecting  himself  to  experi- 
ment, to  the  rank  of  lieutenant  colonel,  the  number  of  medical  officers 
in  that  grade  being  increased  by  one  for  that  purpose ;  also  his  name 
and  effigy  should  appear  on  the  monument  to  Walter  Reed. 

Dr.  Jesse  W.  Lazear  was  the  third  member  of  the  commission. 

Dr.  Lazear  was  a  native  of  Baltimore  and  a  graduate  of  Johns  Hop- 
kins University,  afterwards  getting  his  professional  degree  at  Columbia 
University  and  Bellevue.  At  the  time  he  incurred  his  death  in  the 
course  of  these  experiments,  as  above  mentioned,  he  was  34  years 
old.  He  left  a  wife  and  two  young  children,  the  younger  a  little  son 
born  a  few  months  before  his  death,  whom  he  never  saw.  Mrs.  Lazear 
received  from  Congress  a  pension  of  $17  a  month  with  $2  additional 
for  each  of  two  minor  children  until  they  reach  the  age  of  16.  Also 
a  battery  in  Baltimore  Harbor  was,  by  direction  of  the  Secretary  of 
War,  named  in  his  honor.  It  is  believed  that  this  recognition  on  the 
part  of  the  nation  for  his  services  is  utterly  inadequate.  His  widow's 
pension  should  be  increased  to  $100  a  month,  and  steps  should  be 
taken  to  perpetuate  his  name  in  connection  with  the  Walter  Reed 
monument  above  suggested. 

Dr.  A.  Agramonte  was  the  fourth  member  of  the  Yellow  Fever 
Commission.  He  was  a  Cuban  by  birth,  an  immune  to  yellow  fever, 
and  having  been  assigned  other  work,  took  no  part  in  the  first  series 
of  experiments  with  regard  to  the  conveyance  of  the  disease  by  the 
mosquito,  of  which,  in  fact,  he  was  not  at  the  time  cognizant.  Being" 
an  immune,  he  ran  no  risk  in  connection  with  this  work,  and  it  is 
believed  that  his  contributions  to  it  have  been  sufficiently  recognized 
in  the  association  of  his  name  with  the  other  members  of  the  com- 
mission who  brought  about  this  great  discovery. 

Twenty-three  of  the  men  who  submitted  themselves  for  experiment 
by  the  board  contracted  yellow  fever,  beginning  with  Dr.  James  Car- 
roll, who  was  taken  sick  August  31,  1900,  and  ending  with  John  R. 
Bullard,  who  was  taken  sick  October  23,  1901. 

Conspicuous  among  them  was  John  J.  Moran,  a  civilian  clerk 
employed  at  the  headquarters  of  Gen.  Fitzhugh  Lee,  at  Quemados, 
who  was  one  of  the  earliest  volunteers  for  the  second  set  of  experi- 
ments, and  whose  action  was  dictated  by  the  purest  motives  of 


22  -IX>W  FEVER, 

altruism  and  self-devotion.     Mr.  Moran  disclaimed,  before  submit  t  in*: 
to  the  experiments,  ai  ,  and  has  never  accepted 

.  ahhou-li  he  was  olleivd  the  $200  which  the  liberality  of  the 
military  gov  .abled  the  commission  to  give  to  each  <  \ 

mental  pat  inn.  the  members  of  the  board  excepted.  Such 
modesty  that  he  has  made  no  effort,  so  far  as  known  to  this  olliee,  to 
make  known  his  connection  \\ith  these  experiments  and  reap  the 
is  so  justly  dne  him.  Mr.  Moran  was  a  native  of  Ohio. 
His  proem  address  is  not  kno\\n  to  t  his  ollice.  The  first  inoculations 
in  thecaseol  f«>r  some  reason  unsuccessful.  <>n  Novem- 

ber 26  and  29.     Ho  did   not    suifer  an  attack   until   after  the  third 
inoculation,  on  December 

The  same  remarks  apply  to  the  lir.-t  experimental  case  of  the  second 
set,  Pvt.  John   K.   K  hospital   corps,  who  volunteered    at    the 

same  time  \\ith  Moran  and  equally  disclaimed  anv  doire  for  re\\ard. 

Pvt.    l\i  — iii'j'T  did   not   leave  Cuba  immediately  after  the 
inents.  as  , lid  Mr.  Moran.  and  tl  'lie  military  author!. 

able  to  reward  him  in  some  measure  alon«:  with  other  e  men 

who  volunteered   for  these  experiments.      lie  was   promoted    acting 
hospital  steward,  presented  with  a  gold  watch  by  the  chief  surgeon 
of  the  department  in  the  presence  of  all  the  medical  officers  and 
pital  c,.rps  men  on  duty  at  Columbia  Barracks,  and  also  re 
present  of  $115  in  cash.     He  took  his  discharge  November  14,  1 
and  has  since  (on  December  17,  1903)  made  application  for  pen-ion. 
This  was  refused  for  lack  of  evidence  that  his  ill-health  was  incident 
to  the  service. 

Of  the  other  experimental  cases,  seven  were  Spanish  immi^r 
who  submitted  to  experiments  purely  for  the  money  which  t ! 
promised.     With  regard  to  those  who  were  American  soldiers,  how- 
ever, 10  in  number,  in  addition  to  those  already  mentioned,  ii 
not  be  doubted  that,  although  they  received   pecuniar. 
desire  to  assist  in  what  they  appreciated  was  a  great  and 
work,  together  with  a  spirit  of  adventure,  was  th-  rful 

motive.     The  same  is  true  of  the  last  experimental  ca-e.  Mr.  John  K. 
Bullard,  a  graduate  of  Harvard,  where  he  was  a  distinguished  at 
and  captain  of  the  university  crew.     The  names  of  en,  with 

the  dates  of  then*  attack,  is  appended  with  t!ii>  rep 

It  remains  to  mention  Dr.  Rooert  P.  Cook,  actii  banl  SUIL 

and  the  six  privates  of  the  hospital  corps,  who  were  for  -jn  n 
shut    up   in   the  infected    bedding  house  at  Camp    La/ear.     'I 
experiments,  which  were  absolutely  necessary  to  demonstrate 
vellow  fever  could   not  be  carried  otherwise  than  by  the  n 
had  for  these  men,  so  far  as  they  knew,  an  e<jual  element  « 
with   the  other  experiments   and    had    in    addition    Mich    : 

disagreeable  features  as  to  test  to  the  full  their  hardihood  and 
••nee.     Much  of  the  balding  upon  which  they  ^-lept   and  which 
ttter  were  required  daily  to  handle,  was  so  soiled  with  the  di 

of  the  -ick  as  to  be  •  '   >  the  n«»se  and  eye.  and 

experimenters  actually  slept  in  the  pajamas  and  >hert  -.  which  had 
been  worn  by  severe  cases  of  yellow  fever.     The  names  of 
men  are  appended  to  the  list  given  below  of  experimental 
yellow  fever. 

It  will  be  observed  that   three  of  these  men      Folk.  .1.  ami 

— afterwards    submitted    to    the    nioM|iiito    inoculation    or 


YELLOW   FEVER. 


23 


blood  injection  in  order  to  demonstrate  their  nonimmunity  at  the 
time  of  the  first  experiment. 

It  is  believed  that  the  names  of  all  the  Americans  on  this  list 
should  be  placed  on  a  tablet  in  connection  with  the  monument  to 
Walter  Reed. 

From  the  foregoing  it  will  be  seen  that  the  total  disbursements, 
of  this  great  nation  in  the  way  of  rewards  for  those  who  made  possible 
this  discovery  and  their  families,  amounts  to  $146  a  month.     As  to] 
its  value  to  the  American  people  attention  is  invited  to  the  quota- 
tions from  Gen.  Wood  and  Prof.  Welch  given  above,  and  others  given 
in  the  inclosed  circulars  published  by  the  Walter  Reed  Memorial 
Association. 

How  discreditable  appears  this  niggardly  provision  when  com- 
pared with  the  action  of  the  English  Government  which  more  than 
a  century  ago,  when  the  purchasing  power  of  money  was  far  greater 
than  at  present,  gave  to  Jenner,  the  discoverer  of  vaccination,  grants 
amounting  to  £30,000  sterling.  He  also  received  from  a  subscrip- 
tion in  India  £7,383  sterling,  while  the  Reed  Memorial  has  so  far 
succeeded  in  raising  only  a  little  over  half  that  sum. 

It  is  believed  that  if  the  President  would  exert  his  great  personal 
influence  in  furtherance  of  the  aims  of  that  association  its  task 
would  be  soon  completed. 

R.    M.    O'REILLY, 

Surgeon  General,   United  States  Army. 


Names  of  persons  who  submitted  to  experimental  inoculation  of  yellow  fever,   Cuba, 

1900-1901. 


Infected  by  mosquitoes. 

James  Carroll Aug.  31, 1900 

X.  Y.  (American  soldier) Sept.    6,1900 

John  R.  Kissinger Dec.     8, 1900 

Nicanor  Fernandez Dec.  13, 1900 

5     Antonio  Benigno Do. 

Becente  Presedo Dec.  15, 1900 

John  J.  Moran Dec.  25, 1900 

Jose  Martinez... Jan.     3,1901 

LeviE.Folk Jan.    23,1901 

Clyde  L.  West...  Feb.     3,1901 

James  L.  Hanberry Feb.     9,1901 

Charles  G.  Sonntag Feb.  10, 1901 

13  Pablo  Ruiz  Castillo Sept.  19,1901 

14  Jacinto  Mendez  Alvarez . Oct.    13, 1901 

Infected  by  injection  of  blood. 

1  Warren  G.  Jernegan..  ..  Jan.     8,1901 

2  William  Olson Jan.    11,1901 

3  Wallace  Forbes...  Jan.    24,1901 

4  JohnH.  Andrus Jan.    28,1901 

5  Manuel  Gutierrez  Moran ...          Oct.   20, 1901 

John  R.  Bullard Oct.    23, 1901 

Infected  by  injections  of  filtered  blood  serum. 

1  P.  Hamann,  Twenty-third  Battery  Coast  Artillery Oct.    19,1901 

2  A.  W.  Covington,  Twenty-third  Battery  Coast  Artillery Do. 

Exposed  to  fomites. 

1  Dr.  R.  P.  Cooke,  acting  assistant  surgeon 

2  LeviE.Folk.........  

Warren  G.  Jernegan 

4  James  L.  Hanberry 

5  Edward  Weatherwalks  (bitten  once,  negative;  refused  after  Hanberry  came  down) . 
James  Hildebrand  (offered  himself,  but  was  declined  on  account  of  age) 

7     Thomas  M.  England ..  


Taken  sick. 


(    H  M'TKK    4. 

• 

YELLOW-FEVER  COMMISSION. 
[Senate  Document  No.  S20,  Sixty-first  Conureas.  woond  session  ] 

WAI:   DKPAI:  IMKN  i  . 
OFFICE  OF  TH  \L, 

jtfon,  April  29,  1910. 

MY  DEAR  SENATOK:   It   irive-  m«-  irreat   pleasure  to  comply  with 
the  re»|ue>t  contained  in  your  In  \  |>nl  _'».  to  furni-h  you  With  a 

report  of  the  occurrence^  which  led  to  the  appointment  of  the  \ello\\- 
t  omission,  of  which  Maj.  Walter  Keed  \\a^  presidi  !  the 

names  of  the  pe  >imerted  with  the  experiments  of  tlie  (-(.in- 

mission,  together  with  other  data  which  i<  available  concernim:  t  hem. 

Surg.  Gen.  Sternberg  was  for  many   years  one  of    tlie   leading 
auth  ;i  the  world  on  the  subject  of  yellow  fever,  and  had  made, 

under   the   direction    of   the   President    of   the    t'nited    Stab 
laborious  investigations  as  to  its  cause  in  Ilak-ma.  Bra/il.  and  Mexico. 
These  investigations  were  UIIMH  <  -e—  ful  because,  as  we  now  know,  tin- 
organism  of  yellow  fever  is  invisible  to  the  micro>c..pe.   but    they 
served  a  valuable  purpose  in  enabling  Dr.  Sternberg  to   dU| 
the  claims  of  other  investigators  to  have  discovered  the  causative 
organism  and  to  have  prepared  protective  inoculations  ajrainM   the 
disease.     His  attention  n  a  ving  been  attracted  by  the  claim  of  Sana 
relli,  of  Buenos  Aires,  to  have  discovered  the  cause  of  yellow 
in  the  Bacillus  icteroides,  he  ordered  Maj.  Keed.  at   that   time  pro- 
fessor of  bacteriology  in  the  Army   Medical  School,   to  study   this 
organism  in  connection  with  an  organism  discovered   by  Stern  her*: 
in  t  he  bodies  of  yellow-fever  patients  in  llabana.  and  name<l  by  him 
bacillus  X.     This  investigation  was  continued  by  a  board  run-Mini: 
of  Maj.  Walter  Reed,  surgeon,  United  States  Army,   and   A 
Asst.    Surgs.    James    Carroll,    Aristides    Ai;ramonte.    and    Jo-e    \\  . 
Lazear,  United  States  Army,  which  was  appointed  t<>  meet  at  (amp 
inbia,  near  Habana,  Cuba,  in  May,   !!>()().     The  instruction-  to 
Maj.  Kced,  president  of  this  board,  included  the  following: 


You  will  naturally  give  special  attention  to  qu.  iiini:  i«»  ili«-  <  -ti..!..^  and 

prevention  of  yellow  iever.     As  you  are  familiar  \viih  \\liai  has  aln-ady  Keen  done  by 
other  bacteriologists  in  (fait  field  of  imrwtigation,  I  ^\»\\,,\  r..n.-i<l«-r  it  aeceflBaryto 
you  any  suggestions  or  detailed  i  n-i  ru<  ii  irident  that  the  mo0t  imp 

Question  which  will  occupy  your  attention  is  that  \vhi«-h  relates  t«»  ih«-  <  -liolo^y 

•  h-'-a-.- 

You  will  also  take  advantage  of  such  <.|.|><>rt  unit  if*  an  may  <»fi.  -r  f.  .r  i  h. 
infectious  diaeanes,  and  e«pecially  of  the  mai  ;n_-  in  the  i-lan-1  <>i 

An  important  queetioD  Ln  connection  with  the  diMaaee  of  toopical 
al  cou  nines  relates  lo  1  1;  i>rilcatta'  fouhuh 

Htrangers  are  especially  Hiil.  j«!      sh-.u'1  ..!••  ..p|...r 

luriiry  for  i  h«-.  -t  ud  y  of  leprosy  in  tip  ^pital  in  i  A  m-nf  i»ii 

should  also  be  given  to  ih*  n, 
prevail,  the  etiology  of  which  has  u<-  :mii.  ly  determined. 

24 


YELLOW  FEVER.  25 

One  member  of  the  board,  Dr.  Aristides  Agramonte,  lived  in 
Habana,  and  another,  Dr.  Jesse  W.  Lazear,  was  already  stationed  at 
Columbia  Barracks,  having  joined  there  on  February  13,  1900.  The 
remaining  members  of  the  board  arrived  in  Cuba  June  25,  1900. 
They  were  able  to  prove  conclusively  that  in  18  cases  of  unmistakable 
yellow  fever  investigated  from  beginning  to  end  bacillus  icteroides  was 
not  present  and  that  this  organism  could  not  be  the  cause  of  the  dis- 
ease. These  conclusions  were  diametrically  opposite  to  those  of  Drs. 
Wasdin  and  Geddings,  of  the  Marine-Hospital  Service,  who  likewise 
at  that  time  were  studying  yellow  fever  in  Habana,  and  who  con- 
firmed the  findings  of  Sanarelli.  The  board  then  proceeded  to  investi- 
gate the  theory  advanced  by  Finlay,  that  yellow  fever  was  conveyed 
by  mosquitoes.  A  full  history  of  these  experiments  has  been  pub- 
lished in  the  reports  of  the  board,  and  a  brief  account  of  it,  together 
with  a  list  of  the  persons  who  submitted  to  experimental  inoculation, 
was  given  in  a  memorandum  prepared  for  the  President  by  this  office 
on  August  30,  1906,  and  transmitted  as  a  special  message  to  Congress 
on  December  5,  1906.  It  was  published  as  Senate  Document  No.  10, 
Fifty-ninth  Congress,  second  session,  a  copy  being  inclosed. 

Before  taking  up  individually  the  men  concerned  in  these  experi- 
ments, in  order  to  state  what  is  known  about  them  at  the  present 
time,  it  may  be  mentioned  that  the  Spaniards  who  were  inoculated 
did  so  for  the  pecuniary  inducement  offered  them.  After  receiving 
the  reward  offered  them  by  the  liberality  of  the  military  government 
of  Cuba,  $200  for  each  person  successfully  inoculated,  they  passed 
from  the  scene  and  nothing  further  is  known  concerning  them. 
While  their  names  should  be  preserved  as  a  matter  of  historical 
interest,  it  is  considered  that  they  have  been  well  rewarded  for  their 
share  in  the  matter,  especially  as  the  idea  of  assisting  in  the  advance- 
ment of  science  was  not  a  controlling  motive  for  their  action.  Also 
it  should  be  stated  that  it  can  not  be  demonstrated  that  these  experi- 
ments caused  the  death  or  subsequent  ill  health  of  any  of  the  partici- 
pants, with  the  exception  of  Dr.  Lazear  and  of  three  individuals  who 
died  in  the  course  of  the  experiments  which  were  conducted  by  Maj  . 
Gorgas  and  Dr.  John  Guiteras  at  Las  Animas  Hospital,  Habana, 
between  February  and  December,  1901,  which  will  be  referred  to  later. 

In  view  of  the  facts  which  have  come  to  the  attention  of  this  office 
since  the  preparation  of  the  memorandum  for  the  President,  it  is 
believed  that  that  memorandum  does  not  do  justice  to  the  importance 
of  the  part  which  Dr.  Agramonte  took  in  these  investigations.  Dr. 
Agramonte  has  made  the  following  statement  with  regard  to  the 
work  of  the  board, 


In  the  investigations  of  the  board  with  reference  to  Bacillus  icteroides, 
had  the  bacteriological  work,  Dr.  Agramonte  _tbf>  aujgvpiya.nd  gross  pathology,  Dr. 
.n-ssf  \Y.  Lazear  the  microscopical  pathology. 

"InTune,  lyuu,  Ur.  Agramonte  was  senl  to  the  city  of  Santa  Clara  to  investigate  the 
outbreak  of  yellow  fever  in  that  city,  and  in  July  he  was  sent  to  the  city  of  Pinar  del 
Rio  to  investigate  the  outbreak  of  yellow  fever  among  the  American  troops,  which 
the  surgeons  stationed  there  had  failed  to  recognize  as  such.  Dr.  Agramonte  promptly 
recognized  the  true  character  of  the  disease,  and  was  joined  there  by  Maj.  Reed  a 
couple  of  days  later.  It  was  there  that  for  the  first  time  the  probability  of  mosquito 
agency  in  transmitting  the  disease  was  seriously  discussed  by  members  of  the  board, 
and  it  was  decided  to  carry  out  some  research  in  this  direction. 

As  Dr.  Lazear  had  obtained  considerable  training  in  mosquito  work  while  in  Italy, 
and  none  of  the  other  members  of  the  board  had  any,  it  was  agreed  that  he  take  up 
this  part  of  the  work  in  the  beginning.  Dr.  Carroll  continued  to  investigate  the 
bacteria  and  Dr.  Agramonte  the  pathological  anatomy  of  yellow  fever. 


26  YELLOW  FEVER. 

Maj.  Reed  at  this  time  returned  to  Washington  for  the  purpose  of  com  plot  in 
report  upon  "Typhoid  Fever  in  the  Army,"  in  collaboration  \v  hakeepeare 

La*ear  began  to  breed,  dissect,  classify.  and  equitoes,  in  which  work  Carroll 

and  Agramonte  took  little  <>r  no  part.    Now  and  then  Lazear  would  apply  tl 

1 
and  several  other  persona  had  been  bitten  .-e\eral  times  by  mosquitoes  \ 

.  vioualy  had  ft*.  1  tat  1  ho  theory  « 

transmission  was  gradually  I  'I.  until  Carroll  fell  the  :J«uh  <>f 

AUL.VSM  •  !'"*>  .  entirely  inn..,  ,  ,,i  ,,f  the  real  nature  «-f  his  illn.—  -. 

Suspecting  the  or  .  "s.  Lazear  and 

inonte  d»  .  h  presumably  had  caused  Carroll's  att:i 

.  app  hr>t  nonimmune  individual  \vh«»  miuht  all'.w  \\. 

31,  the  sai  were 

applied  to  an  A 

•  !  id  he  ir«»  out  of  said  reser- 
vation before  1, 
our  minds  the  fa-  1  that  he  had  been  im"e«-ied  i.\  the  mcequi  to  bites, 

Dr.  '  :M«>  Mill  Hit'fen:  severe  al  ••»  disease, 

Drs.  Lazear  and  Agramonte  decided  to  communicate  these  results  to  Maj.  Reed,  who 
was  >  ton. 

n>  Maj.  Reed's  arrival  in  Tlabana,  Dr.  Lazear  became  infected  w 
i  taking  place  on  the  25th  of  September. 

Dur  !'s  convalesce)  i  ard  decided  that  the  resi 

tion  were  so  far  sufli  'ivincini,'  to  justify  their  pre>- 

preliminary  note.  before  the  coming  meeting  of  the  American  Publ 
at  Indianapolis,  Ind.  (October,  1900). 

Reed  went  north  for  this  purpose,  and  while  Carroll  took  a  short  va 
recuperate  from  his  recent  attack,  Dr.   Airramonte  v,  i  with  br< 

:inir  rni.sijuitoes,  keeping  them  at  the  division  laboratory,  -which  was  under  his 
care  in  Habana,  in  preparation  for  the  work  which  the  board  intended  to  carr 
after  the  Indianapolis  meeting. 

When  Maj.  R<-ed  returned  from  the  States,  moral  and  m  1  was  obt: 

from  Gen.  Leonard  Wood,  commanding  the  division,  and  we  determined  to 
out  an  investigation  exclusively  based  upon  the  mosquito  il 

we  knew  nothing  of  Beauperthuy  then,  who  in  1853  had  defended  practically  the 
same  theory. 

While  th'e  experimental  station,  afterward  named  Camp  Lazear,  in  honor  i« 
memory  of  our  deceased  colleague,  was  being  established,  the  care  of  the  moe<j 
and  their  infection  by  applying  them  to  yellow-fever  cases,  way  in  i 
Agramonte,  at  the  division  laboratory:  when  the  permanent  ••mosquito  building"  was 
erected  at  Camp  Lazear  (Dec.  1,  1900),  these  mosquitoes  were  tun  m  Dr. 

Carroll  for  his  care.     It  devolved  then  upon  Dr.  Agramonte  to  wlect  the  mos. 
from  those  kept  by  Dr.  Carroll  and  apply  them  to  nonimmunes,  as  well  a-  t«.  make  all 
subsequent  direct  inoculations,  and  to  obtain  the  nonimmunes  (Spaniards)  f 
purpose,  until  the  end  of  the  work  in  Cuba. 

Let  me  add  that  the  best  friendship  existed  between  all  the  m.  "oard, 

and  from  the  beginning  of  their  work  it  was  a-re.  <1  thai  the  Imnnr  ol  Itn  was 

to  be  shared  by  all  alike,  as  the  labor  was  so  evenly  nhan  <1.     I  - 
not  been  the  case,  let  us  hope  through  no  fault  of  tl 

Reed  and  Carroll  had  been  connected  in  laboratory  work  I  years,  and  Dr. 

Agramonte  had  also  worked  at  the  Army  Medical  Museum  l.aborat.  >•  Lazear 

and  Agramonte  were  classmates,  having  graduated  from  the  College  of  MS  and 

Surgeons,  New  York,  in  June  1892. 

T<>  the  absolute  truth  of  the  above  statement 

In  testimony  whereof  I  affix  my  signature  in  the  August  :\\,  1908. 

ARISTIDEH  A-  M    I  > 


1.  Mai.  Waltor  Rood,  surpM.n.  I'mic*!  -  \  rm\  .  <lir<l  in  Well- 
ington, I                          andicitb,  November  51.     Hi- 
widow.  Knii                     Reed,  is  receiving  a  pension  of  $125  a  month. 

2.  llaj.  James  Carroll  was  promoted  iv  licutcm-nt  i 
by  special  act  of  Congress  March  '.»,  P.»n7.     H(>  'I"1'  I  in  ^';i 

l>.  <  ..  of  myoninlilk  Scplrinl.  Jennie   II. 

nth, 

apj.  \rinv  appropriation  hill. 


YELLOW   FEVER.  27 

3.  Dr.  Jesse  W.  Lazear,  contract  surgeon,  United  States  Army,  died 
at  Camp  Columbia,  Cuba,  of  yellow  fever,  September  25,  1900.     His 
widow,  Mabel  M.  Lazear,  since  his  death  has  received  an  annuity  of 
$125  a  month,  appropriated  from  year  to  year  in  the  Army  appropria- 
tion bill. 

4.  Dr.  Aris tides  Agramonte  is  the  only  living  member  of  the  board. 
He  is  professor  of  bacteriology  and  experimental  pathology  in  the 
University  of  Habana  and  has  never  received,  either  directly  or  indi- 
rectly, any  material  reward  for  his  share  in  the  work  of  the  board. 

5.  The  name  of  the  American  soldier,  XY,  who  was  the  subject  of 
the  second  experiment,  was  concealed  at  the  time,  because  the  experi- 
ment was  macte  without  military  authorization.     It  has  been  recently 
ascertained  to  be  William  H.  Dean,  private,  Troop  B,  Seventh  Cav- 
alry.    He  has  never  received  any  reward.     He  was  discharged  August 
17,  1902,  by  reason  of  expiration  of  term  of  service,  and  there  is  no 
further  record  of  him  at  the  War  Department.     His  residence  at 
enlistment  was  given  as  Grand  Rapids,  Mich.     His  case  has  special 
importance  as  having  been  the  first  experimental  case  which  was  com- 
plete in  the  matter  of  control,  for  Dr.  Carroll's,  which  came  four 
days  earlier,  was  defective,  by  reason  of  his  going  into  the  infected 
zone  during  the  period  of  incubation. 

6.  John  R.  Kissinger,  private,  Hospital  Corps  (see  p.  6,  President's 
message).     Kissinger  volunteered  for  service  at  the  beginning  of  the 
Spanish  War  in  Company  D,  One  hundred  and  fifty-seventh  Indiana 
Volunteers,  and  after  his  discharge  enlisted  in  the  Hospital  Corps. 
After  the  first  secret  experiments  of  the  board,  which  included  the 
cases  of  Dr.  Carroll  and  Pvt.  Dean,  became  known  and  the  experi- 
mental camp  was  established  and  named  Camp  Lazear,  Kissinger 
and  Moran  were  the  first  to  volunteer  as  subjects  for  experiment. 
Moran  was  first  bitten,  but  Kissinger  was  the  first  to  be  attacked,  on 
December  8,  1900.     He  recovered  and  was  afterwards  promoted  to 
be  acting  hospital  steward,  and  discharged  November  14,  1901,  at 
Columbia  Barracks,  Cuba.     It  is  understood  that  his  health  after- 
wards failed  so  that  he  became  entirely  dependent  upon  -the  labor  of 
his  wife  for  support.     He  was  pensioned  at  the  rate  of  $12  per  month, 
by  the  act  of  March  2,    1907.     This   amount  is  considered  quite 
inadequate  either  for  his  support  or  as  a  recognition  of  his  services. 
A  bill  granting  an  increase  to  $125  per  month  was  favorably  reported 
and  incorporated  in  Senate  bill  6272  and  passed  the  Senate  February 
15,  1910,  but  was  objected  to  by  the  Committee  on  Pensions  of  the 
House  of  Representatives.     The  report  of  the  Senate  committee  (No. 
574)  is  inclosed. 

7.  John  J.  Moran  (see  p.  6,  President's  message).     Mr.  Moran  has 
never  received  any  material  reward  for  his  most  creditable  services. 
After  leaving  Cuba  he  completed  his  education  by  a  course  of  study 
at  the  University  of  Virginia,  and  is  at  present  living  at  Panama,  in 
the  employ  of  the  Isthmian  Canal  Commission.     He  is  at  present  an 
applicant  for  appointment  in  the  Consular  Service  for  which,  by  reason 
of  his  excellent  knowledge  of  Spanish  and  other  qualifications,  he  is 
well  fitted. 

8.  Levi  E.  Folk,  private,  Hospital  Corps,  volunteered  to  be  bitten 
by  infected  mosquitoes  and  was  taken  with  yellow  fever  January  23, 
1901.     He  is  still  in  the  military  service,  and  is  a  sergeant,  Hospital 
Corps,  stationed   at  the  recruit  depot,  Columbus  Barracks,  Ohio. 


28  YELLOW  FEVBE. 

He  received  a  donation  of  $300  from  the  appropriation  made  by  Gen. 
Leonard  Wood  for  ;  :»eriments. 

9.  Clyde  L.  \Ye-t.  pn\  pital Corps,  volunteered  to  he  hit  ten 
hy  infected  -            toes  at  (  nd  was  taken  >i«-k  \\ith 
yellow  fever  Februa-                 !.      II,-  \\a>  di-char<:ed  from  tli. 

July  10,  1902,  at  Fort    M\.  I  his  subsequent   addiv 

unki  \  «-d  .-i  donation  of  $200  from   the  appropriation 

made  by  Gen.  Leonard  Wood  for  the>e  experiments. 

10.  James  L.  Han  private,  Hospital  Corps,  volunteered  to 
be  bitten  by  infected  mosquitoes,  and  in  lence,  was  taken  -i.  k 
with  yellow  fever  at  Camp  La/car  Kehruary  '.»,  1901.     He  des< 
the  service  April  4,  190'J.  at  the  general  hospital.  \Va-hin.Lrton 
racks,  D.  C.     His  subsequent  addre»  is  unknown.     II  ed  a 
donation  of  $300  from  the  appropriation  made  by  Gen.  Wood  for 
these  experiments. 

11.  Ch;  Sontag,  private,   llo-pital  Corps,  volunteered  to  he 
hitten   hv  infected    mosquitoes,    and    was   in   consequence    taken 

with  yellow  fever  at  Camp  Lazear  Fehniaiv  in.  p.»ni.  He  was  dis- 
charged from  the  service  Deeemher  1'J.  UMI'I.  ;1t  Columhia  Barracks, 
Cuba,  and  hl8  Subsequent  address  is  unknown.  He  iv.eived  a  dona- 
tion of  $200  from  the  appropriation  made  by  ( Jen.  Leonard  Wood  for 
these  experiments. 

12.  Warren    Gadsden    Jernegan.    private.     lh»pital    Corps,    was 
infected  with  yellow  fever  hv  the  injection  of  blood,  and  taken  >iek 
January  8,  1901.    He  was  discharged  November  16,  r.»<  !um- 
bia  Barracks,  Cuba.     Address  given,  care  olM.  A.  Fouler.  MeMeekin, 
Fla.     He  received  a  donation  of  $300  from  appropriation  made  by 
Gen.  Wood  for  these  experiments. 

I.S.William  Olsen,  private,  Hospital  Corps,  was  infected  with 
yellow  fever  by  injection  of  blood,  at  Camn  Lazear,  and  taken  ^i<  k 
January  11,  1901.  He  was  discharged  November  15,  1901.  at 
Columbia  Barracks,  Cuba.  Address  given,  care  of  C.  Olsen.  Plum 
.  Wis.  He  received  a  donation  of  $200  from  the  appropriation 
made  by  Gen.  Wood  for  these  experiment  -. 

14.  Wallace  W.  Forbes, private,  Hospital  Corps,  volunteered  to  be 
infected  with  vellow  fever  by  the  injection  of  hlo<'d.  at  ( !amp  I A 
and  became  sick  January  24,  1901.     lie  was  di-(hai_:ed   March   1, 
1905,  at  Fort  Hancock,  N.  J.    Address  given.  <  -'.  W.  For 

Minneapolis,  Minn.     This  soldier  received  a  donation  of  $200  1 
the  appropriation  made  by  Gen.  Wood. 

1").  John  II.  Andrus,  private,  Hospital  Corps,  volunteered  and  was 
infected  with  yellow  fever  by  injection  of  hlood.  at  Camp  and 

became  sick  January  28,  1901.     He  was  discharged  April  1M,  i 
at  Camr>  Geo.  H.  Thomas,  Chickamauga,  Trim,     lli-  -ul>-r<jurnt 

address  is  not  known.  He  received  a  donation  of  S'Jnn  from  the 
appropriation  made  by  Gen.  Wood. 

John   R.   Bullard,  native  of  Massadm-i  tuate   of 

vard   Univei  here   he  was  a   di-t  in«:ui>hed    athlete,   and 

eOffagcd    iii    farming    in    <ul>a.    volunteered    and    was    infected    with 
vellow  fever  by  the  injection  of  blood.     He  hecame  sick  OH 
1901. 

1  ,     Paid  I  lamann,  private,  Twenty-third  Comp.  i  tillery. 

vohmteere.I  and  was  infected  with  yellow  fever  h\  injection  of  filtered 
blood  serum  and  became  sick  October  19,  1901 .  He  \\  a 


YELLOW   FEVER.  29 

July  19,  1902,  by  reason  of  expiration  of  term  of  service.  His  address 
given  at  time  of  enlistment  was  care  of  August  Hamann,  Moline,  111. 
Present  address  not  known.  This  soldier  received  a  donation  from 
the  appropriation  made  by  Gen.  Wood  for  these  experiments. 

18.  Albert  W.  Covington,  private,  Twenty-third  Company,  Coast 
Artillery,  volunteered  and  was  infected  with  yellow  fever  by  injection 
with  filtered  blood  serum  and  became  sick  October  19,  1901.     He  is 
still  in  the  service,  and  is  serving  as  sergeant,  Twenty-third  Company, 
Coast  Artillery  Corps,  at  Fort  McKinley,  Portland,  Me.     He  received 
a  donation  from  the  appropriation  made  by  Gen.  Wood  for  these 
experiments. 

19.  Dr.  Robert  P.  Cook  (see  President's  message,  p.  7).     Dr.  Cook 
entered  the  medical  service  June  9,  1900,  as  contract  surgeon,  from 
the  State  of  Virginia.     He  left  the  service  at  his  own  request,  Decem- 
ber 22,  1904.     His  present  address  is  Winchester,  Va. 

The  demonstration  made  by  Dr.  Cook  and  the  men  with  him  that 
yellow  fever  could  not  be  transmitted  by  infected  clothing  and  other 
inanimate  objects  was  of  the  utmost  importance  to  commerce  and 
has  immensely  simplified  the  preventive  measures  to  be  taken  against 
this  disease.  He  was  shut  up  in  a  house  with  infected  bedding  for 
20  days,  together  with  the  following  privates  of  the  Hospital  Corps, 
who  received  a  donation  of  $100  each  from  the  appropriation  given 
by  Gen.  Wood  for  these  experiments: 

20.  Edward  Weatherwalk.     Discharged  the  service  December  12, 
1901,  at  Columbia  Barracks,  Cuba.     Subsequent  address  not  known. 
He  received  a  donation  of  $200. 

21.  James   Hildebrand.     Still  in   service   as   private,   first   class, 
Hospital  Corps;  stationed  at  the  recruit  depot,  Columbus  Barracks, 
Ohio.     He  received  a  donation  of  $100. 

22.  Thomas  M.  England.     Still  in  service  as  sergeant,  first  class, 
Hospital  Corps;  stationed   at   Fort  Ward,  Wash.     He  received   a 
donation  of  $100. 

In  addition  to  these,  Pvts.  Folk,  Jernegan,  and  Hanberry  under- 
went the  exposure  to  infected  bedding  prior  to  being  bitten  by  the 
infected  mosquitoes. 

Additional  experiments  by  Maj.  W.  C.  Gorgas  and  Dr.  John 
Guiteras,  at  Las  Animas  Hospital,  Cuba  (see  vol.  Ill,  p.  386,  civil 
report  of  Gen.  Wood,  1901): 

(1)  Vergera;     Spaniard.     Infected   by   mosquitoes   February   23, 
1901;  recovered. 

(2)  Carro;  Spaniard.     Inoculated  by  infected  mosquitoes  August  8, 
1901;  died. 

(3)  Represas;  Spaniard.     Infected  by  mosquitoes  August  8,  1901; 
recovered. 

(4)  Campa;  Spaniard.     Infected  by  mosquitoes  August  9,   1901; 
died. 

(5)  Taylor,  John  R. ;  Englishman.     Infected  by  mosquitoes  August 
13,  1901;  recovered. 

(6)  Miss  Clara  Louise  Maass,  of  East  Orange,  N.  J.,  aged  25. 
Trained  nurse  in  Las  Animas  Hospital.     She  served  as  trained  nurse 
in  Medical  Department  of  the  Army  during  the  Spanish  War.     She 
volunteered  and  was  bitten  by  infected  mosquitoes  August  14,  and 
died  of  yellow  fever  August  18,  1901. 


30 

(7)  Varela;  Spaniard.     Infected  by  inn>(|uitoos  August    i  l, 
recovered  1 . 

(8)  Alonso;  Spaniard.     Infected  by  mosquitoes  August  2J. 
recoven 

(9)  Castillo;  Spaniard.     Infected   by    mosquitoes   September    16, 
1901,  \>y  l>r.  Carroll;  recovers  1. 

ml.     Infected    1>\     mosquitoes    Novrm!><>r    17, 
1901;  recovti 

The  amount  of  the  donations  received  by  these  volunteers  is  imt 
known. 

•  iv  were  22  cases  of  experimental  Yellow  fever  jn-oduccd  hy  Ueed. 
Carroll,  and  Lazear,  and  Id  in  the  experiment^  ran  in  I  on  in  Ilahana 
by  Gorgas  Hi  Bras.  There  \\ei-e  aUo  7  persons  \\lio  underwent 

the  very  trying  experiment  of  sleeping  in  infe<-ted  be«l<ling. 

It  luis  been  impracticable  to  make  a  complete  list  of  the  persons 
who  submitted  to  the  bites  of  mosquitoes  but  who  failed  to  become 
infected,  although  it  must  be  reco^ni/ed  that  in  many  cases  these 
exhibited  as  hjgfi  a  degree  of  courage  as  those  who  suffered  an  attack 
of  yellow  fever. 

It  is  hoped  that  the  Senator  will  be  able  to  obtain  the  consent  of 
Congress  to  the  erection  of  a  monument  which  will  be  worth 
Maj.  Reed,  who  conceived  and  carried  out  in  so  admirable  a  manner 
these  epoch-making  experiments,  and  to  the  is  who  shared  in 

his  labors  and  to  the  persons  who  offered  their  bodies  for  these  dan- 
gerous experiim  : 

Aery  respectfully,  GEO.    II.  T<>i:\ 

Surgeon  General,  United  States  An 

Hon.  ROBERT  L.  Owi 

United  States  Senator,  Washington,  D.  C. 


[Senate  Report  No.  574,  Sixty-first  Congress,  second  session.] 

The  Committee  on  Pensions,  to  whom  was  referred  the  bill  (S.  7252)  granting  an 
annuity  to  John  R.  Kissinger,  have  examined  the  same  and  report: 

A  bill  granting  an  increase  of  $125  per  month  to, Mm  K.  Kissinger,  the  apt 
herein,  was  favorably  reported  by  your  committee  and  incorporated  in  Senate  hill 
6272  at  this  session  ami  passed  the  Senate  »n  i-VI,niary  l.r>,  1!MO. 

The  Senate  report  No.  210,  which  contains  a  very  full  statemcr  Cervices  of 

this  soldier  and  the  grounds  upon  which  his  right  to  increase  of  pension  is  recogni/< •«  1 . 
is  as  follows: 

S.  4479.  John  Kissinger,  the  claimant,  was  one  of  the  bravest  of  soldiers  who  H 
in  the  Spanish- American  War.     For  exhibition  of  moral  courage  hi> 
inoculation  of  yellow  fever  seems  unsurpassed.     il«-   i-   n..\v  a  helpless 
unable  to  walk,  and  he  is  totally  disabled  for  any  kind  of  employment,  hi-  ailment 
being  rnyel iti-,  or  disease  of  spine,  and  is  the  result  ol  up<>n  him 

when  he  volunteered  to  become  a  subject  for  experimental  purpo-cs  in   the   yell.iw- 
iial  in  Cuba.      At  tin-  lime  h"  made  the  Kierifico  he  was  a  private  in  the 
Hospital  Corpn  of  the  Army,  in  which  heenl,  L898.     \\hen  ho  was 

finally  discharged  from  the  hospital,  h<-  was  app«.int'-d  an  a-  tin/  hospital  M- 
served  as  such  until  the  d.ii<-  of  his  di- 

enlistment  he  served  in  Company  I),  One  hundred  and  fifty-seventh  Indiana  Volun- 
teer Infantry,  from  April  2",  1898,  to  Noven  i  i  .ni:  enli.-ted  in 
at  the  breaking  out  of  the  war  with  Spain,  and  in  response  to  President  Me  Kin  ley  a 
call  for  troops. 

The  commission  that  investigated  the  mosquito  theory  oi  llou 

fever  in  the  fall  of  1900  was  composed  of  Dre.  Walter  i;.-«'d,  James  Carroll,  and  Jesse 
W.  Lazear.    From  a  book  entitled  "Walter  k«-«-d  and  V-  II  '      Howard 

A.  Kelly,  professor  of  surgery  of  the  Johns  1  i  'Diversity,  published  in  New 


YELLOW   FEVER.  31 

York  by  McClure,  Phillips  &  Co.,  on  page  139,  is  the  following  paragraph  in  regard 
to  this  soldier: 


humanity  and  the  cause  of  science. '  When  it  became  known  among 
troops  that  subjects  were  needed  for  experimental  purposes,  Kissinger,  in  company 
with  another  young  private  named  John  J.  Moran,  also  from  Ohio,  volunteered  their 
services.  Dr.  Reed  talked  the  matter  over  with  them,  explaining  fully  the  danger 
and  suffering  involved  in  the  experiment  should  it  be  successful,  and  then,  seeing  they 
were  determined,  he  stated  that  a  definite  money  compensation  would  be  made  them. 
Both  young  men  declined  to  accept  it,  making  it,  indeed  their  sole  stipulation  that 
they  should  receive  no  pecuniary  reward,  whereupon  Maj.  Reed  touched  his  cap, 
saying  respectfully,  'Gentlemen,  I  salute  you.'  Reed's  own  words  in  his  published 
account  of  the  experiment  on  Kissinger  are:  'In  my  opinion  this  exhibition  of  moral 
courage  has  never  been  surpassed  in  the  annals  of  the  Army  of  the  United  States.'" 

Dr.  Lazear  died  of  yellow  fever  in  Cuba  at  that  time.  Dr.  Carroll  died  later  of 
disease  resulting  from  yellow  fever  contracted  during  his  experiments  with  that 
trouble.  Dr.  Walter  Reed  is  also  dead,  and  the  widows  of  these  three  men  have  all 
been  remembered  by  the  Government  in  an  annuity  of  $125  per  month.  On  account 
of  the  death  of  these  doctors,  soldier  is  unable,  of  course,  to  furnish  any  further  evi- 
dence from  them,  but  his  volunteer  submission  to  inoculation  from  infected  mosqui- 
toes is  a  matter  of  record  in  the  archives  of  the  War  Department. 

He  is  now  receiving  a  pension  of  but  $12  per  month,  and  he  can  obtain  no  further 
relief  because  he  is  unable  to  furnish  direct  testimony  tracing  his  present  grievous 
condition  back  to  yellow  fever  in  the  Army,  although  there  is  but  little  doubt  that 
the  relation  of  the  cause  and  effect  exists.  Since  his  discharge  he  has  never  been  in 
good  health,  which  he  at  first  attributed  to  slow  recovery  from  that  disease,  thinking 
that  with  the  passing  of  time  his  constitution  would  enable  him  to  throw  it  off.  He 
continued  to  fail,  however,  and  is  now -a  helpless  paralytic.  In  the  meantime  he 
had  married,  and  is  now  supported  by  his  small  pension  and  laundry  work  done  by 
his  wife  and  contributions  to  his  support  by  a  few  people  who  appreciated  his  services 
to  humanity. 

A  bill  to  grant  him  a  pension  of  $30  per  month  passed  the  House  during  the  session 
of  the  Fifty-ninth  Congress,  but  by  mistake  the  rate  was  cut  to  $12  per  month,  at 
which  amount  it  was  finally  approved.  In  his  present  helpless  condition  it  is  believed 
that  he  is  entitled  to  a  highly  substantial  measure  of  relief,  his  disability  seemingly 
being  due  to  causes  of  service  origin. 

In  view  of  the  fact  that  a  pension  or  annuity  of  $125  per  month  was  granted  to  the 
widows  of  Drs.  Lazear  and  Carroll,  who  conducted  these  experiments  with  yellow- 
fever  infected  mosquitoes,  and  who  died  as  a  result  of  being  infected  by  mosquitoes, 
your  committee  are  of  the  opinion  that  as  great  consideration  should  be  given  to  the 
man  who  braved  the  danger  and  who,  while  he  escaped  with  his  life,  is  so  helplessly 
crippled  that  he  is  unable  to  do  anything  to  care  for  himself,  as  to  the  widows  of  Drs. 
Lazear  and  Carroll.  Your  committee  therefore  recommend  in  this  case  a  pension 
or  annuity  of  $125  per  month. 

The  bill  went  to  the  House  and  was  referred  to  the  Committee  on  Pensions.  There 
the  paragraph  increasing  the  pension  to  the  applicant  herein  was  objected  to  as  carry- 
ing a  rate  in  excess  of  that  allowed  to  any  other  private  soldier  and,  regarded  simply  as 
a  pension  and  without  distinguishing  language,  establishing  a  vexing  precedent.  , 

The  facts  in  this  case  are  exceptional  and  extraordinary.  To  meet  the  exceptional 
case  and  obviate  the  objections  the  pending  bill  recites  the  peculiar  circumstances 
that  distinguish  the  case  and  proposes  an  annuity  of  $125  per  month,  payable  by  the 
Secretary  of  War  in  the  same  manner  as  the  same  allowances  are  now  paid  to  the 
widows  of  Drs.  Carroll  and  Lazear.  In  view  of  the  unprecedented  facts  in  the  case 
and  the  extraordianry  services  rendered  by  the  soldier,  your  committee  believe  he 
should  receive  the  same  recognition  accorded  the  widows  heretofore  mentioned.  The 
bill  is  therefore  reported  back  favorably  with  a  recommendation  that  it  pass. 


u  5. 
IN  MEMORIAM. 

DR.  WALTER   REED,  MA.IMI:    AND    M  I:<;K<>\.   i  \riT.I)  STATES   AltMV. 

Whereas  the  Medical  Society  of  the  District  «'f  Columbia  has  sus- 
tained an  irretrievable  loss  by  the  death  of  Walter  Kced,  who  died 
at  2  p.  m.,  November  2::.  from  appendicitis,  for  which  an  oper- 

ation  had  been  performed  H\e  d 

Beitresokeds  That  in  the  death  of  Dr.  Reed,  the  medical  society 
has  lost  one  of  its  mo<t  di-tinLruishcd  member  i»  best  efforts 

were  always  at  its  di-po-al  and  upon  whom  it  had  learned  to  rely  as 
an  able,  calm,  and  accurate  exponent  of  scientific  medicine. 

Maj.  Reed  was  born  in  Glou.  County,   Va.,  Sepiem 

1851,  and  was  a  graduate  of  the  medical  depart  mont  of  tho  t'nivt'isity 
of  ^'irlrinia,  1869,  and  Bollcvno  Jlosnital  M«-di.-al  C..HCL  II.' 

was  appointed  assistant  surgeon,  rintrd  States  Anny,.hine  26,  1  B75j 
promoted  assistant  snr«roon,  with  (he  rank  of  captain,  June  26,  1880; 
surgeon,  with  rank  of  major,  December  4,  IS'.):-;,  and  at  the  time  of  his 
death  was  first  on  the  list  of  majors  in  the  Medical  Department. 

He  served  with  distinction  as  medical  officer  at  various  Armv 
posts  in  the  Far  West,  and  as  his  skill  and  devotion  extended  to  hotli 
officers  and  enlisted  men  alike,  he  endeared  himself  to  all  claac 
the  command. 

During  his  service  at  Fort  McHenry,  Md.,  in  1881,  and  again  while 

nding  surgeon   and   examiner  of  recruits   at   Ba! 
October,  1 890,  to  October,  1891,  he  made  special  stud  ie>  in  bac 
and  pathology  at  the  Johns  Hopkins  Hospital,  and  alter  u  to 
service  at  Fort  Snellmg  and  St.  Paul,  he  was  >ele<  i,  ,1  !,\  the 
Greneral,  in  August,  1893,  as  curator  of  the  Army  Medical  Mu 
where  he  continued  his  studies  which  ultimately  secured  for  him  fa  mo 
and  distinction. 

During  the  Spanish-American  War  he  was  president  of  the  board 
of  medical  officers  to  investigate  and  report  on  the  j»i;  \alen 
typhoid  fever  in  the  Army,  and  the  commission,  strongly  inmr- 
with  the  agency  of  flies  as  carriers  of  this  disease,  recommended  the 
collection  of   excreta  in  galvanixod-iron   tanks,   which   method  was 
adopted  and  was  followed  by  a  cessation  of  the  disease. 

His  greatest  achievement  for  science  and  humanity  was  his  con- 
tribution to  the  cause,  spread .  and  prevention  of  \  ellnw  f. 
ing  from  Finlav's  theory  of  the  a-.  n<  y  of  the  nioxpiiio  in  the  dis- 
semination of  tnis  disease,  the  coin  mission  of  which  Dr.  Kecd  was  the 
head  made  a  series  of  pain-ta  i.eriments  and  demonstrated 

conclusively  the  causal  relation  of  Stegomyia^asciata  to  yellow  i 
epidemics  and  disproved  the  theory  that  the  disease  could  oe  conveyed 
mfomites,  or  that  it  vraa  oontagtatu  in  the  ordinary  acceptation  of  the 
term. 

*  The  preamble  and  resolution  ware  adopted  December  3,  1902. 


YELLOW  FEVER.  33 

The  practical  value  of  this  discovery,  which  in  point  of  importance 
and  far-reaching  beneficence  ranks  only  second  to  Jenner's  discovery 
of  vaccination,  has  been  proved  by  the  complete  eradication  of  this 
scourge  from  Habana. 

Maj.  Reed  has  demonstrated  how  to  rid  the  world  of  yellow  fever, 
but  his  studies  as  to  the  etiology  of  the  disease  were  interrupted  by 
his  untimely  death;  he  had,  however,  arrived  at  the  conclusion  that 
the  disease  was  not  due  to  Sanarelli's  Bacillus  icteroides,  but  was 
probably  caused  by  some  ultramicroscopic  organism.  Dr.  Reed  was 
a  clear,  forceful  writer  and  speaker;  all  of  his  facts  were  collected  with 
the  utmost  care  and  presented  in  a  concise,  logical,  and  convincing 
manner,  and  his  crowning  work  shows  the  highest  degree  of  scientific 
accuracy,  combined  with  calm  judgment  and  discrimination,  qualities 
which  are  not  only  of  the  utmost  importance  in  searching  the  causes 
of  epidemic  diseases  and  tracing  their  progress,  but  which  would  have 
also  fitted  him  for  the  highest  position  in  his  corps. 

In  every  sphere  of  activity,  whether  as  a  medical  officer,  author, 
teacher,  or  investigator,  he  has  acquired  a  distinction  which  rightly 
places  him  in  the  first  rank  of  illustrious  American  physicians. 
His  labors  in  behalf  of  science  and  humanity  have  been  recognized 
by  Harvard,  Ann  Arbor,  and  the  American  Medical  Association, 
and  he  has  borne  his  Honors  with  accustomed  modesty  and  innate 
dignity.  Dr.  Reed  was  singularly  free  from  all  mean  self-interest 
and  ambition,  and  was  ever  ready  to  give  full  credit  to  his  col- 
leagues for  their  share  of  the  work  which  made  him  famous.  We 
have  simply  to  recall  his  glowing  tribute  to  that  brave  young  soldier 
Kissinger,  from  Ohio,  who  on  December  5,  1900,  was  the  first  to 
volunteer  to  be  bitten  by  infected  mosquitoes,  with  the  only  provision 
that  he  should  receive  no  pecuniary  reward,  since  as  he  expressed  it, 
he  was  actuated  "solely  in  the  interest  o'f  humanity  and  the  cause  of 
science. "  Such  exhibition  of  moral  courage,  in  the  opinion  of  Dr. 
Reed,  has  never  been  surpassed  in  the  annals  of  rhe  Army  of_£tie 
United  Stales,  and  we  will  add,  could  never  have  been  inspired  except 
by  a  man  of  Dr.  Reed's  greatness. 

"His  lips  are  silent;  no  longer  will  the  sound  of  his  musical  but 
decisive  voice  be  heard  within  these  walls,  nor  his  personal  mag- 
netism and  discerning  mind  delight,  instruct,  and  charm  his  listen- 
ers, but  his  deeds  will  live  and  his  example  will  be  an  inspiration 
to  the  present  and  future  generations. 

Dr.  Reed's  death  in  the  prime  of  life,  in  the  zenith  of  his  dis- 
tinguished career,  is  a  severe  blow  to  scientific  medicine,  his  corps, 
and  the  medical  profession  which  he  adorned.  This  society,  while 
expressing  the  sincerest  grief  at  the  loss  of  our  distinguished  associate, 
whose  personal  qualities  commanded  our  highest  friendship  and 
respect,  is  not  unmindful  of  the  irreparable  loss  sustained  by  his 
beloved  family,  to  whom  we  beg  to  offer  our  heartfelt  sympathy  in 
the  hour  of  their  great  affliction,  united  with  the  fervent  hope  that 
a  grateful  Nation  will  recognize  the  economic  value  of. Dr.  Reed's 
discovery  and  make  adequate  provision  for  those  who  were  dependent 
upon  him  for  support. 

GEO.  M.  KOBER, 
D.  K.  SHUTE, 
F.  S.  NASH, 

Committee. 
79965°— S.  Doc.  822,  61-3 3 


34  Yri.I.OW     l-T.YKR. 

MEMORIAL  MEETING  OP  THB  MEDU  v  OF  THE  DISTRICT  OP  COLUMBIA,  nn  n 

DECEMBER  31,  1902. 

INTRODUCTORY   ADDRESS  BT  SAMUEL  8.  ADAMS,   A.   M.,   M.   D.,   PRESIDENT 

Ladies  and  gentlemen:  Once  more  we  have  been  railed  together 

to  pay  tribute  to  the  nuMiiory  of  an  honored  colleague,  whose  counsel 
we  have  enjoyed  for  nearly  a  «leeade.  The  possessor  of  a  striking 
personality .  unusual  reasoning  power,  an  unbiased  judgment,  ami  a 
determination  to  enforce  his  convictions,  Dr.  Walter  Reed  could  not 
fail  to  adorn  and  stimulate  this  >cientilic  body  as  well  as  the  inilitary 
seryiceof  the  I'nited  States  Army.  The  aged  die,  and  we  wonder  not, 
believing  that  they  have  fulfilled  their  mission;  but  when  a  colaboivr 
in  the  prime  of  life,  at  the  height  of  his  usefulness,  is  cut  down  before 
he  has  had  time  to  enjoy  the  full  fruition  of  his  labors,  we  marvel, 
we  are  lost  in  wonder. 

Dr.  Keed  was  elected  a  "member  by  invitation"  March  11.  1894. 
The  preceding  meeting,  however,  he  made  his  first  appearance  in 
society,  having  been  invited  to  open  the  discussion  on  Dr. 
Kinyoun's  paper,  entitled  "The  prevention  and  control  of  dinh- 
theria."  In  reverting  to  this  debate,  we  can  recall  his  mo. lest 
demeanor,  his  convincing  arguments,  and  his  power  to  hold  his  audi- 
ence throughout  a  lengthy  presentation  of  trie  subject.  He  1 
by  saying  that  his  clinical  experience,  laboratory  work  in  inoculating 
animals,  and  bacteriological  studies  had  led  him  to  certain  ideas  as 
fixed  convictions: 

1.  The  Klebs-Loeffler  bacillus  is  usually  characterized  by  a  depM>ii 
of  false  membrane  in  the  throat  and  is  attended  by  frequent  1 
sequela?.     This  bacillus  he  believed  to  be  the  cause  of  true  primary 
diphtheria. 

2.  That  diphtheria  is  local  in  the  beginning  and  by  the  production 
of  virulent  toxins  tends  to  become  rapidly  constitutional.     The  bacilli 
themselves  have  been  found  in  the  internal  organs  of  the  human 
subject,  as  well  as  in  those  of  animals.     So  that  we  can  not  any  longer 
say  that  the  bacilli  remain  local  throughout  the  attack. 

3.  Diphtheria  is  not  spread  by  water  and  food,  except   by  milk 
and  its  products,  which  are  infected  in  transit u.     He  strongly  advo- 
cated the  bacteriological  examination  in  making  the  diagnosis. 

Two  months  later,  in  discussing  tuberculosis,  he  dwelt  upon  these 
two  points:  "The  possibility  of  the  transference  of  tuberculosis  by 
vaccination;  and  trie  possibility  of  its  transference  from  mother  to 
child  in  utero." 

January  9,  1895,  in  discussing  diphtheria  and  its  treatment  by  its 
antitoxin,  he  said  he  believed  the  production  of  antitoxin  should  be 
under  municipal  control  and  be  tested  by  disinterested  parties  so  as  to 
avoid  imposition  by  unscrupulous  men  whose  desire  is  gain.  He 
lived  to  see  the  enactment  of  a  law  to  protect  this  community  from 
spurious  viruses.  He  had  witnessed  the  wonderful  iininuni/ing 
effects  of  Antitoxin,  so  advised  its  use  as  a  preventive  as  well  as  a 
curative  agent. 

Ills  masterly  hand  struck  the  death  blow  to  the  opponents  of  anti- 
toxin in  the  discussion  of  "The  clinical  aspects  of  diphtheria  treated 
by  its  arn  December  4,  1895. 

A  clinician  of  wide  experience  and  recognized  ability,  while  dis- 
claiming any  unfriendliness  toward  its  use,  had  taken  a  decided  stand 


YELLOW  FEVER.  35 

against  this  serum,  basing  his  remarks  upon  the  statistics  and  argu- 
ments of  a  distinguished  English  laryngologist  and  a  well-known 
American  pediatrist.  It  seemed  as  if  the  pendulum  were  swinging 
toward  the  opposition  when  Walter  Reed  entered  the  forum — majes- 
tic, fearless,  determined  to  conquer.  With  keen  eyes  fixed  on  his 
principal  antagonist,  he  hurled  his  weapon  of  defense  in  unmistakable 
language,  when  he  said : 

You  are  theorizing  while  we  are  dealing  with  facts.     If  another  friend  of  antitoxin 

arises  and  deals  it  such  blows  as  Dr. has  given  it,  the  antitoxin  serum  will  be 

slaughtered  in  the  house  of  its  friends. 

In  concluding  his  remarks,  came  this  appeal: 

I  myself  almost  feel  like  saying,  with  the  reader  of  the  paper,  that  the  failure  to  use 
it  in  a  case  of  human  diphtheria  is  criminal;  and  I  beg  of  you,  that  if  you  have  not  yet 
done  so,  when  you  next  stand  by  the  bedside  of  your  patient  afflicted  with  this  disease, 
you  do  not,  through  any  fear  of  its  peculiar  action,  withhold  this  invaluable  remedy. 

It  must  have  been  a  great  satisfaction  to  him  to  witness  not  only 
the  conversion  of  his  opponents,  but  the  universal  use  of  the  anti- 
toxin of  diphtheria. 

His  paper  entitled  "What  credence  should  be  given  to  the  state- 
ments of  those  who  claim  to  furnish  vaccine  lymph  free  from  bac- 
teria?" is  worthy  of  praise.  He  conducted  a  series  of  experiments 
upon  monkeys  by  vaccinating  them  with  various  vaccine  matter, 
and  was  "  convinced  that  all  virus  contained  bacteria  and  that 
bacteria-free  lymph  did  not  exist." 

It  is  a  singular  coincidence  that  the  last  appearance  of  Dr.  Reed 
in  this  society  was  at  a  memorial  meeting,  when  he  eulogized  as 
an  author  his  friend  and  associate,  Dr.  W.  W.  Johnston. 

The  Medical  Society  of  the  District  of  Columbia  is  proud  of  hav- 
ing had  the  friendship  of  Walter  Reed;  we  gloried  in  his  achievements, 
and  we  now  mourn  the  loss  of  a  courteous,  industrious,  famous,  and 
highly  honored  member. 

HISTORICAL    REMARKS,  BY    MEDICAL    DIRECTOR   R.  A.  MARMION,  UNITED  STATES  NAVY. 

Mr.  President  and  members  of  the  Medical  Society  of  the  District 
of  Columbia:  Walter  Reed  was  born  in  Gloucester  County,  Va.,  on 
the  13th  of  September,  1851,  and  was  the  son  of  Rev.  Lemuel 
Sutton  Reed,  who  was  for  40  years  or  more  an  eminent  Methodist 
minister.  In  his  personal  appearance  Walter  was  highly  favored 
even  in  his  youth,  and  to  this  there  were  added  a  gentleness  of  dis- 
position and  a  graciousness  of  manner  which  won  for  him  the  admira- 
tion of  all  who  were  brought  in  contact  with  him — qualities  which  we 
know  were  characteristic  of  him  ever  after.  Intellectually  he  was, 
as  a  boy,  precocious  and  devoted  to  study,  so  that  at  the  age  of  15 
he  had  acquired  a  knowledge  of  Latin  and  Greek  rarely  found  in  one 
so  young.  History,  literature,  and  philosophy  were  also  favorite 
studies,  and  his  familiarity  with  them  rendered  him  the  peer  of  many 
who  were  his  seniors  in  age  by  several  years. 

By  a  special  dispensation  he  was  matriculated  in  the  academic  de- 
partment of  the  University  of  Virginia  at  the  age  of  16.  He  quickly 
attained  and  held,  throughout  that  first  year,  the  highest  standing  in 
his  classes.  Owing,  however,  to  the  limited  means  of  his  father,  who 
was  maintaining  two  other  sons  at  the  same  school,  it  became  evident 
to  Walter  that  he  would  not  be  able  to  carry  out  his  original  plan  of 
completing  the  academic  course;  so,  at  the  beginning  of  the  following 


36  YELLOW   FEVER. 

year  he  began  the  study  of  medicine,  and  at  the  end  of  one  session  of 
nine  months  he  was  awarded  the  dome  of  doctor  of  medicine,  although 
he  was  not  yet  18  years  of  age.  This  feat  he  accomplished  in  snite 
of  tin'  advice  of  friends  who  had,  in  advance,  sought  to  di»uade  him 
from  undertaking  it.  His  only  reply  to  such  advisor-  waa  that  "he 
did  not  result."  In  a  few  months  after  his  graduation  at  the 

rniversitv  of  Virginia  he-  went  to  New  \  ork  and  matriculated  at   the 

BeUevue  Medical  College,  and  in  one  s«v-  (iiired  tl 

M.  D.  Following  his  graduation  at  Bellevue  he  was  attached  to 
various  hospitals  in  New  York  and  Brooklyn,  conspicuously  the 
Brooklyn  City  Hospital  and  the  Charity  Hospital  on  Bftadcwell'fl 
Island;  at  t  he  latter  he  devoted  himself  especially  to  the  study  of  the 
diseases  of  women  and  children.  He  was  also  for  awhile,  one  of  the 
0  the  poor  of  New  York  City.  During  his  Brooklyn  life 
he  had  attracted  the  attention  of  Dr.  Joseph  Hut  chins*  »n,  one  nf  the 
most  prominent  medical  men  of  that  city,  who  urired  and  secured  his 
appointment  as  one  of  the  five  inspectors  of  the  board  nf  healt: 
position  much  sought  after  in  those  days.  This  post  he  was  filling 
most  creditably  when  his  twenty-first  "birthday  dawned.  Kven  at 
this  early  date,  Dr.  Heed  had  acquired  a  very  enviable  standing 
among  the  medical,  men  of  New  York  and  Brooklyn,  among  whom 
he  was  especially  well  known  for  his  skill  as  a  surgeon.  Within  . 
years,  as  we  have  seen,  he  had  been  holding  various  professional  ; 
tions  of  responsibility,  but  he  could  not  help  feeling  that  there  was  a 
point  beyond  which  he  could  not  go  on  the  road  toward  that  sii 
which  he  coveted,  without  the  influence  of  wealthy  friends  and  of  in- 
fluential social  connections  on  the  spot.  Thus  it  was  that  in  187 -1  he 
began  to  think  seriously  of  entering  the  Medical  Corps  of  the  Army  or 
of  the  Navy,  and,  by  the  spring  of  1875,  he  had  chosen  the  Army  as 
the  field  of  his  future  labors. 

I  can  not  dismiss  this  part  of  my  subject  without  pausing  for  a 
moment  to  weigh  certain  characteristics  of  our  lamented  colleague 
and,  first  of  all,  I  would  advert  to  the  fact  that  even  in  his 
hood  years  there  shone  forth  so  many  of  the  splendid  traits  which 
illustrated  his  after  life;  he  was  firea  with  ambition  and  sustained 
by  an  indomitable  energy  in  his  early  student  day-  \\hi.h  invari- 
ably brought  him  victory;  but  his  innate  tenderness  of  nature  and 
his  exquisite  regard  for  the  sensibilities  of  a  disappointed  emit  extant 
so  dominated  him  at  such  times  that  no  one  ever  knew  him  to  1 
of  his  victory.    A  deference  for  the  opinions  of  others,  too,  \\  a-  a  1 
a  prominent  characteristic;  and  this  we  have  seen  rvincrd  so  uni- 
formly in  the  discussions  taking  place  at  meetings  of  this  so< 
And  so  I  might  go  on  analyzing  and  dwelling  upon  other  tr. 
but  the  limited  time  prevents  me. 

Turning  to  the  military  history  of  Maj.  Walter  Keed.  as  home 
upon  the  records  of  the  office  of  the  Surgeon  General  of  the  Army, 
we  find  that  he  was  appointed  it,  surgeon  with  the  rank  of 

first  lieutenant  June  26,  1875;  promoted  to  be  a*- Mam 
with  the  rank  of  captain  June  26,  1880;  surgeon  with  rank  nf  major 
December  4,  1893;  and  at  tin-  time  of  his  death  was  first  on  the  li-t 
of  majors  in  the  Medical   Department. 

He  was  on  duty  in  the  Department  nf  the  East  from  duly  '23,  1875, 
to  May  21,  1876;  in  the  Depart  merit  nf  Ari/onu  from  June,  1876,  to 
May,  1880;  again  in  the  Department  of  the  Kast  from  September, 


YELLOW  FEVER.  37 

1880,  to.  November,  1882.  From  November,  1882,  to  July,  1887, 
he  was  attached  to  the  Department  of  the  Platte,  and  from  August, 
1887,  to  October,  1890,  he  was  on  duty  at  Mount  Vernon  Barracks, 
Ala.  His  next  assignment  was  to  duty  in  Baltimore,  Md.,  from 
October,  1890,  to  October  1891,  when  he  was  transferred  to  the  De- 
partment of  Dakota,  where  he  remained  until  August,  1893,  when  he 
was  ordered  to  duty  in  the  office  of  the  Surgeon  General  of  the  Arnry. 
Under  this  assignment  he  was  curator  of  the  Army  Medical  Museum 
and  member  of  the  faculty  of  the  Army  Medical  School  for  over  nine 
years  and  up  to  the  date  of  his  death,  which  occurred  in  this  city 
November  23,  1902. 

In  the  meantime,  too,  he  served,  at  several  different  periods,  as 
member  of  the  Army  Medical  Board  in  this  city,  was  a  member 
of  the  cholera  board  in  July,  1898;  was  on  detached  duty  making 
inspections  of  camps  and  field  hospitals  in  August,  1898;  was  member 
of  the  typhoid  fever  board  in  August,  September,  and  October,  1898; 
in  October,  1898,  he  was  on  inspection  duty  at  Natural  Bridge,  Va., 
and  again  in  April  and  May,  1899,  at  Puerto  Principe,  Cuoa.  In 
March  and  April,  1900,  he  was  ordered  to  investigate  and  report 
upon  the  use  of  electrozone  and  germicides  at  Tampa  and  Habana, 
and  in  June  and  July,  1900,  was  a  member  of  a  board  of  medical 
officers  at  Camp  Columbia,  Cuba,  for  the  purpose  of  scientific 
investigation  with  reference  to  infectious  diseases  prevalent  in  Cuba, 
and,  from  September  27  to  October  13,  1900,  on  similar  duty  with 
regard  to  yellow  fever.  These  various  assignments  were  of  great 
importance  from  the  standpoint  of  preventive  medicine  and  did 
much  to  solidify  the  foundation  on  which  he  was  destined  to  erect 
the  structure  "more  lasting  than  brass"  which  to-day  towers  above 
the  many  works  of  a  life  full  of  labors  for  the  benefit  of  his  fellow 
man. 

It  seems  to  me  that  I  can  not  better  close  this  paper  than  by 
quoting  the  language  of  the  official  record  of  Maj.  Keed  as  drawn 
from  the  files  of  the  Surgeon  General's  Office : 

Of  Maj.  Reed's  work  in  the  Medical  Department  and  his  scientific  researches,  it 
is  probable  a  complete  history  can  never  be  obtained.  His  eminence  as  a  bacteri- 
ologist, and  in  practical  hygiene  as  applied  to  military  life  (as  a  student  of  all  forms  of 
bacteria)  led  to  his  being  intrusted  with  special  investigations,  which  were  interrrupted 
by  his  death,  and  which,  it  is  now  believed,  will  never  be  completed.  He  was 
regarded  by  his  associates  as  a  man  who  combined  an  unusual  degree  of  scientific 
accuracy  with  calm  judgment,  which  rendered  him  invaluable  in  searching  out  the 
causes  of  epidemic  diseases  and  tracing  their  progress. 

In  1901  he  began  the  investigation  of  the  cause  and  the  prevalence  of  yellow  fever, 
conducting  his  investigations  at  Quemados,  near  Habana,  where  he  established 
headquarters  and  was  given  every  facility  for  conducting  his  experiments. 

The  conditions  in  Cuba  in  1901  were  such  as  made  the  investigations  of  Maj.  Reed 
and  his  corps  of  assistants  of  special  moment.  An  epidemic  of  yellow  fever  existed 
despite  the  efforts  of  the  sanitary  experts,  led  by  Gen.  Wood,  who  were  endeavoring 
to  stamp  out  the  disease.  The  houses  of  persons  infected  were  subjected  to  rigid 
disinfection.  Furniture  was  destroyed  and  every  possible  precaution  was  taken  to 
prevent  the  spread  of  the  disease  under  the  old  treatment.  Maj.  Reed  became  con- 
vinced that  proper  sanitation  was  not  all  that  was  needed.  He  believed  that  some 
other  agency  than  accumulations  of  filth  was  responsible  for  the  spread  of  the  disease, 
and  his  attention  was  attracted  to  the  fact  that  it  took  much  longer  for  a  house  to 
become  infected  than  the  usual  time  of  incubation.  This  suggested  a  biting  insect 
as  an  intermediate  host  of  the  parasite,  and  he  asked  and  promptly  received  from 
Gen.  Wood  permission  to  make  experiments  with  mosquitoes  as  the  conveyers  of 
yellow  fever,  and  a  liberal  supply  of  money  for  these  experiments.  It  was  thus 
determined  beyond  question,  that  through  a  certain  species  of  mosquito  the  yellow 
fever  germ  was  disseminated. 


38  YELLOW  FEVER. 

In  recognition  of  this  precious  work  the  degree  of  master  of  arts 
was  conferred  upon  Maj.  Reed  by  the  Harvard  University  in  ,June. 
1902,  because,  as  President  Eliot  stated  when  the  degree  was  awarded, 
Maj.  Reed  had  demonstrated  how  to  rid  the  world  of  \ello\\  fever, 
About  the  same  time  the  degree  of  LL.  D.  was  conferred  upon  him 
he  University  of  Michigan  at  Ann  Arhor.  Midi. 

MAJ.    REED  A8  A   MEDICAL  OFFICER,    BY   MAJ.   J.    R.    KEAN,    SURGEON,    UNITED  81 


In  speaking  of  Dr.  Reed  as  a  medical  ofliccr  we  should  consider 
especially  that  part  of  \ii^  career  with  which  the  members  of  this 
society  are  least  familiar,  namely,  from  his  entrain -c  into  the  Army 
in  1875  to  his  assignment  to  duty  in  Washington  in  is(.»:;.  With 
the  latter  date  began  his  career  as  a  scientific  man,  although  mm-h 
of  his  time  during  this  la-t  decade  was  given  to  examining  boards 
and  other  work  of  a  military  rather  than  scientific  character,  and  the 
race  horse  spent  much  tune  at  the  plow. 

The<e  1  s  years  of  garrison  duty  were,  we  may  be  sure,  not  wasted, 
the  official  records  tell  but  little  of  them.  The  records  show  I  "> 
changes  of  station  (with  4  years  in  Arizona,  5  in  the  Department  of 
the  Platte,  2  in  the  Department  of  Dakota,  3  in  the  South,  and  :;  in 
the  East).  There  are  a  few  brief  commendations  for  professionn ! 
and  devotion  to  his  patients,  and  that  is  all. 

The  work  of  young  Army  surgeons  claims  always  little  spaee  in  the 
gazettes  or  in  the  reports  of  military  commanders,  and  in  the  seven t  ies 
and  eighties  the  hie  was  certainly  not  stimulating  to  intellectual 
effort. 

The  surgeon  shared  with  his  comrades  of  the  line  the  tedium  of 
long  marches  and  the  monotonous  sameness  of  Arizona  summers  and 
Dakota  winters.  And  those  with  whom  bonne  camaraderie  out- 
weighed studious  industry  shared  also  the  afternoons  of  hottlepool 
and  beer  and  the  nightly  seductions  of  draw  poker.  But  for  medical 
officers  this  life  was  redeemed  by  the  study  of  our  profession,  which 
was  then  beginning  to  broaden  out  from  ancient  channels  into  the 
full  flood  of  recent  progress,  and  it  was  saved  from  triviality  l>\  those 
stern  responsibilities  of  life  and  death  which  practice  hrin.irs  to  all 
physicians.  To  lesser  minds  the  limitations  of  such  a  life  niiirht  have 
been  narrowing,  but  for  the  eager  industry  and  professional  d< -\  <>t  i,,n 
of  a  Reed  they  made  the  roots  strike  deep ;  and  when  we  are  su  ij 
at  the  rapid  growth  and  splendid  fruit  of  his  career  as  a  scientist  we 
must  remember  that  in  the  post  surgeon's  unmarked  life  the 
germinated  and  the  roots  were  firmly  set.  But  for  the  opportunities 
given  him  by  his  position  in  the  Army,  however  distinguished  he  may 
have  become  in  other  ways,  it  is  safe  to  say  that  the  \\ork  \\ith  whicn 
his  fame  will  always  be  inseparably  connected  would  n< 
been  accomplished  bv  him.  During  this  lon#  apprenticeship  he 
acquired  too  that  perfect  familiarity  with  the  conditions  and  limita- 
tions of  Army  life  which,  combined  with  his  scientific  knowledge 
sound  judgment,  made  him  the  hot  sanitary  inspector  in  the  Army 
and  the  court  of  last  resort  on  all  sanitary  questions. 

I  first  learned  to  know  Dr.  Reed  by  reputation  when  in  the  spring 
of  1888  I  followed  him  in  .station  at 'Fort  Kol-in-oii.  a  t  \\o-ha  1 1  alion 
po>t  in  the  northwc-t  corner  of  \ehraska.  I  learned  much  of  his 
devotion  to  his  patients,  and  their  devotion  to  him  was  equally 


YELLOW  FEVEE.  39 

in  evidence.  The  country  about  is  thinly  settled  with  families 
locally  known  as  "Grangers/'  who  were  attempting  to  support 
themselves  by  farming  in  a  grazing  country  where  the  rainfall  was 
not  sufficient  for  good  crops  except  only  about  one  year  in  three. 
The  crop  of  babies,  however,  never  failed,  and  the  Klebs-Loeffler 
bacillus  and  the  pneumococcus  flourished  perennially  in  their  wretched 
cabins.  To  Reed's  tender  and  generous  spirit  the  call  of  these  poor 
people  never  came  in  vain,  and  the  trail  was  never  so  long  or  the 
night  so  dark  as  to  deter  him.  In  the  winter  these  rides  were  really 
dangerous  and  a  source  of  much  uneasiness  to  his  family  and  friends 
for  fear  of  his  being  overtaken  by  one  of  those  blizzards  in  which 
the  staunchest  horse  turns  tail  to  the  wind  and  the  most  experienced 
frontiersman  can  not  see  his  way,  and  the  danger  to  the  lost  traveler 
is  greater  than  that  of  a  battle. 

Again  we  find  him  at  Mount  Vernon  Barracks  in  Alabama,  accord- 
ing to  the  official  statement  of  his  commanding  officer,  devoting 
himself  with  the  same  earnestness  and  patience  to  the  sick  of  Geroni- 
mo's  band  of  Apaches,  then  held  there  as  prisoners,  and  to  the  sick 
negroes  of  the  surrounding  country,  as  to  his  own  patients  in  the 
garrison. 

Of  the  first  years  of  his  service  which  he  spent  in  Arizona  I  gained 
some  knowledge  when  in  the  summer  of  1896  he  came  to  Key  West, 
my  station  at  that  time,  to  study  the  blood  of  variola — there  being 
an  epidemic  of  smallpox  there  at  that  time.  All  day  he  would 
sit  over  his  microscope,  but  the  evenings  we  spent  on  the  coolest 
corner  of  the  porch  looking  out  at  the  quiet  tropical  sea,  while  he 
told  reminiscences,  suggested,  it  may  be,  by  the  heat,  of  his  service 
at  Fort  Yuma  and  Camp  Apache.  These  stories  were  full  of  that 
humor  which  was  so  characteristic  and  so  pleasing  a  trait  of  his 
daily  conversation,  and  some  of  these  were  models  of  the  short 
story.  The  history  of  Sally  Ann,  a.  Gila  monster  (named  after  the 
two  ladies  of  the  post  most  conspicuous  in  church  work),  which  the 
chaplain  captured  in  his  kitchen,  and  undertook  to  tame,  would 
have  made  a  perfect  magazine  article  just  as  Reed  told  it.  His 
account  of  his  summer  at  Yuma,  the  hottest  of  Army  posts,  where 
the  daily  July  maximum  was  from  112°  to  115°,  still  brings  back  a 
clear-cut  picture  to  my  memory,  and  I  can  see  him  with  his  messmate, 
a  captain  of  infantry,  who  weighed  250  pounds,  and  the  soldier — or 
in  Army  parlance  "striker" — who  filled  the  dual  role  of  chef  and 
butler.  The  captain,  a  vertiable  Porthos,  sat  down  to  dinner  in 
two  garments,  with  a  fan,  a  towel  to  wipe  his  face,  and  near  at  hand 
a  pitcher  of  the  largest  size  full  of  water  from  the  olla,  for  there 
was  no  ice.  Before  him  was  a  large  roast  of  range  beef,  which, 
after  helping  Reed,  he  would  consume  entirely  and  likewise  empty 
the  water  pitcher. 

On  one  occasion  Reed  took  a  leave,  and,  in  company  with  another 
officer  and  a  lady  of  the  garrison  going  home,  drove  in  an  ambulance 
150  miles  to  the  railroad.  The  other  officer  was  charged  with  the 
commission  of  laying  in  the  food  for  this  trip  of  nearly  a  week.  After 
they  started  they  found  that  the  provision  consisted  simply  of  crack- 
ers and  sardines.  Reed  up  to  that  time  had  never  been  able  to  eat 
sardines,  but  he  learned  on  this  trip.  He  had  his  share  also  of  Indian 
campaigning,  and  on  one  occasion  brought  into  the  post  a  little  Indian 
girl  of  4  or  5,  who  had  been  so  horribly  burned  that  her  people  had 


40  YELLOW  FEVEB. 

abandoned  her  to  die.     This  child  ho  succeeded  in  saving  and  brought 

:p  in  his  family  as  a  nurse  for  his  children  in  spite  of  the  warning 

of  that  keen  old  Indian  lighter,  Gen.  Crook.     When  she  was  i:ro\\n. 

savage  Apache  blood  a  it -elf.  and  she  ran 

giving  evidence  that  15  years  of  p -ntl« -ness  and  refinement  had  not 
modified  the  cruel  and  deceitful  charaotftf  of  her  race. 

Memory  often  holds  1110-1  f;iM  to  trivial  things,  but  they  are 
usually  char  So.  though  what  has  come  into  my  mind  to 

tell  you  of  our  «i  nd  is  not  of  weighty  matters:  yet  they  show 

the  "odd  id.'s  of  Army   life  and  show   him   as   he  was     the 

pleasant  comrade,  the  eager  student,  and  the  de\  oted  doetnr.  gentle, 
unselli>h,  modest,  and  brave,  as  the  gentle  and  devoted  . 

:•  this  earned  spirit  and  the  high  purposes  of  his  life  played  ah. 
a  merry  and  kindly  humor  like  the  dancing  lights  and  reflect* 

-urfaceof  a  deep,  swift  river.     It  was  often  keen,  but  tter, 

and  was  his  mo>t  striking  social  characteristic,  as  was  devotion  to  the 
duty  which  was  before  him  the  dominant  feature  of  his  professional 
life.  For  him,  as  for  the  great  Duke— 

The  path  of  duty  was  the  way  to  glory. 

He  that  walks  it  only  thirsting 

For  the  truth,  and  learns  to  deaden 

Love  of  self,  before  his  journey  closes 

He  shall  find  the  stubborn  thistle  bursting 

Into  gloesy  purples,  which  outredden 

All  voluptuous  garden  roses. 

He  that  ever  follows  her  commands 

On  with  toil  of  heart  and  knees  and  hands 

Through  the  long  gorge  to  the  far  li.L'ht,  has  won 

path  upward  and  prevailed. 
Shall  find  the  toppling  crags  of  duty  scaled 
Are  close  upon  the  shining  table-lands, 
To  which  our  God  Himself  is  moon  and  sun. 
Such  was  he — his  work  is  don« 

DR.  WALTER  REED  AS  A  TEACHER,   BY  A.  F.  A.   KINO,  A.  M.,  M.   I>. 

At  the  time  of  the  organization  of  the  United  States  Army  Medical 
School,  in  1893,  Dr.  Reed  was  appointed  pn.fe— ..r  <»f  hacteri« 
and  clinical  microscopy,  and  he  continued  to  fill  this  position 
to  perform  its  duties  most  acceptably  until  the  time  of  his  decease, 
in  N'ovember,  1902. 

Two  years  after  beginning  his  work  in  the  Army  Medical  School 
he  was  elected  professor  of  pathology  and  bacteriology  in  the  medical 
school  of  the  Columbian  University  in  this  city,  and  he  continued  to 
hold  this  position  also  until  the  end  of  his  life. 

If  we  endeavor  to  ascertain  in  a  general  \\a\  what  are  the  require- 
ments necessary  for  anyone  to  become  a  really  -killed    an. I  BU 
instructor  in  any  department  of  knowledge,  and  th«  ourselves 

how  far  Prof.  Heed  possessed  t  hese  qualif icat  ion-,  it  \\ill  at  once  he 
seen  that  the  particular  attributes  necessary  were  preeminently  his 
own. 

To  teach  well  one  must  know  well  the  subject  to  be  taught .  and, 
conversely,  he  who  can  not  explain  a  thin-_r  «  l«  arly  to  somebody  da- 
does not  usually  know  it  well  himself. 

In  the  whole  domain  of  medi/al  science  there  is  probably  no 
subject  more  dif lie ult  and  intricate  than  that  of  pathology,  especially 


YELLOW  FEVER.  41 

when  considered  in  relation  with  bacteriology,  this  latter  being  also 
a  comparatively  new  departure,  and  therefore  bristling  with  the 
unfamiliar  terms  of  a  new  and  labored  nomenclature,  as  every  new 
science  necessarily  must  be. 

Notwithstanding  these  difficulties,  Prof.  Reed,  with  his  well- 
trained  mind  and  cultivated  powers  of  observation,  inspired,  too,  with 
the  spirit  of  research  and  led  on  by  the  charm  of  discovering  new 
principles  and  new  facts,  had  devoted  himself  with  so  much  ardor, 
earnestness,  and  industry  to  the  study  of  his  chosen  sphere  of  thought 
that,  it  may  be  said,  all  difficulties  had  been  trampled  under  his  feet; 
that  he  rose,  step  by  step,  to  higher  and  still  higher  planes  of  knowl- 
edge, until  reaching  an  eminence  where  the  whole  subject  became 
easily  intelligible  in  one  comprehensive  view  and  where  he  himself 
attained  a  complete  mastery  of  his  favorite  theme. 

Having  traversed  the  highways  of  knowledge  himself  he  was 
fully  able  to  lead  his  pupils  along  the  same  paths  and  perhaps  point 
out  to  them  many  short  cuts  which  were  easier  than  the  longer 
distances  and  more  laborious  journeys  originally  pursued  by  him- 
self. It  should  be  remembered  also  that  many  of  these  roads  were 
not  always  the  well-traveled  avenues  of  old  lines  of  thought,  but,  on 
the  contrary,  entirely  new,  strange,  and  perhaps  lonely  ways,  far  out 
in  the  prairies  of  investigation,  where  briars  of  speculation,  weeds 
of  error,  and  the  ignes  f atui  of  false  theories  were  liable  to  obstruct 
and  mislead  the  honest  seeker  for  truth.  It  was  under  these  circum- 
stances that  Prof.  Reed  became  a  trusted  guide  and  counselor.  In 
these  trackless  wastes  of  thought  he  could  not  easily  get  lost  or  take 
a  wrong  direction,  for  in  many  instances  he  was  able  to  say:  "I  made 
these  paths  myself,"  and  he  well  knew  whither  they  would  lead. 

The  successful  teacher,  however,  must  not  only  possess  the  requi- 
site knowledge  and  be  able  to  guide  his  pupils  in  the  best  way,  and 
hold  out  to  them  the  easiest  method  of  obtaining  the  information  for 
which  they  are  in  search,  but  he  should  also  have  the  faculty  of  pre- 
senting the  subject  in  such  a  manner  as  to  hold  their  undivided 
interest  and  attention  by  pointing  out  the  attractive  features  and 
pleasing  aspects  of  the  subject  under  discussion.  Dreary,  indeed, 
would  be  the  road  to  learning  were  it  always  through  thorns,  thistles, 
and  briars,  with  no  flowers  to  charm  and  no  vistas  in  the  forest 
through  which  we  might  at  times  obtain  a  glimpse  of  pleasant  scenes — 
of  sunshine  and  beauty.  Dreary,  and  dull  too,  will  be  the  teacher 
who  continues  his  endless  monotony  of  tiresome  propositions,  with 
no  touch  of  humor  and  no  sparkle  of  wit  to  vary  the  irksomeness  of 
continued  effort  and  awaken  the  flagging  power  of  a  strained  atten- 
tion by  the  pleasant  diversion  of  an  occasional  happy  thought. 

In  this  particular  again  Dr.  Reed  was  singularly  fortunate.  One 
of  his  latest  admiring  pupils  writes  me  that — 

his  lectures,  besides  satisfying  the  zealous  seeker  for  knowledge,  were  spiced  with 
humor  which  was  most  refreshing,  and  which  made  the  relation  between  himself 
and  his  students  a  freer  and  more  sympathetic  one. — Donnally. 

Indeed,  in  whatever  aspect  we  review  Dr.  Reed's  work  as  a  teacher 
and  however  critically  we  single  out  the  several  qualifications  required 
for  the  best  and  most  successful  execution  of  the  teaching  art,  we 
find  Prof.  Reed  happily  endowed  in  a  more  than  usual  degree  with 
these  special  gifts  and  qualifications,  and  which  he  knew  full  well 
how  to  utilize  to  the  best  advantage. 


42  YELl.ou 

During  the  later  years  <>f  Prof.  Reed's  work  in  the  medical  school 
of  the  Columbian  University  he  was  assisted  by  Dr.  James  Carroll,  of 
the  I  n it ed  States  Army,  who  also  accompanied  l>r.  Reed  t.«  llabana, 
and  again  assisted  him  in  their  well-known  experiments  with  mos- 
quitoes and  yellow  fever.  No  one,  perhaps,  was  better  acquainted 
with  Dr.  Reed's  methods  of  teaching  than  Dr.  Carroll,  who  kindly 
writes  me  as  follows: 

Dr.  Walter  Reed  was  respected  and  beloved  by  all  his  pupils.    Always  kind  and 
courteous,  earnest  and  enthusiastic,  he  imbued  them  with  the  same  spirit .  and  i 
.it'lv  commanded  their  respect  and  attention.    A  thorough  nutter  pi  his  nul.jr.-t  and 
of  tne  English  language,  he  treated  the  driest  and  most  difficult  t<>pi<  s  in  HK  h  a  man- 
ner as  to  rvnder  t  h.-in  lucid  and  interesting.    His  marvelous  accuracy  and  clear 

v  detail,  his  charming  personality  and  polished  manner,  made  him  an 
ideal  professor,  of  whom  his  ftnde nts  were  both  fond  and  proud.  ( >f  nervous  trmprra- 
ment,  he  was  quick  to  note  and  resent  the  slightest  laxity  and  inattention;  and  \\ln-n 
it  became  necessary  to  administer  a  rebuke  it  was  implied  rather  lhan  LM\  en  dim  1 1\ , 
his  delica<  :.g  prompting  him  to  soften  the  blow  by  a  subtle  flash  of  \\  it  that 

convulsed  the  class  and  diverted  attention  from  the  culprit.    The  lesson  was  i 
forgotten  by  him  for  whom  it  was  intended,  and  it  was  never  necessary  to  repeat  it, 

•  •  moral  effect  of  the  slightest  manifestation  of  his  displeasure  was  far  pr  • 
could  have  been  the  dread  of  any  other  method  of  reproof.    So  closely  was  h« •  in 
pa  thy  with  his  class  and  so  securely  had  he  engrafted  nimself  upon  their  affe<  t  ion 
their  inquiries  during  his  illness  and  manifestations  of  grief  upon  his  demise  ind 
the  loss  of  a  dear  friend,  guide,  and  counselor  rather  than  a  teacher  of  cold  scieuti tic- 
facts. 

Another  pupil,  Capt.  J.  Hamilton  Stone,  assistant  surgeon,  United 
States  Army,  writes  me  as  follov 

As  a  teacher  Dr.  Reed  always  seemed  to  me  to  be,  first  of  all,  master  of  his  t  V 
His  information  was  so  much  his  own — a  part  of  him,  as  it  were — that  when  i 
given  to  others  it  flowed  forth  with  unadulterated  naturalness,  and  sparkled  with  a 
Keen  interest  which  his  charming  personality  could  not  help  but  lend  it. 
qualities  would  not  permit  his  words  to  fall  upon  deaf  ears.    His  kindly  and  consid- 
erate mien,  together  with  his  universally  acknowledged  high  scientific  attainments, 
won  for  him  both  the  respect  and  admiration  of  his  students.    His  language  was  always 
interesting,  eloquent,  and  well  appointed.    When  at  his  best  his  voice  would  reach  a 
high  falsetto  note,  and  this  was  his  characteristic  method  of  impressing  importai. 
upon  dull  or  indurate  intellects.    His  students  never  feared  niin,  but  from  th- 
regarded  him  with  filial  affection.    Of  patience,  that  special  attribute  of  a  good  teacher, 
he  possessed  an  abundance.    He  was  constantly  at  the  side  of  his  pupil  in  th 
oratory,  advising,  consoling,  encouraging,  and,  above  all,  instructing. 

A  student  of  the  Columbian  University,  Mr.  H.  H.  Donnally, 
remarks  that— 

Dr.  Reed's  lectures  were  models  of  order  and  system.    A  recital  of  the  various  \ 
previously  held  in  the  different  branches  of  pathology  and  bacteriology  always  led  up 
to  and  served  to  emphasize  the  more  recent  and  generally  accepted  theories.     1 1 
historic  reviews  the  student  was  constantly  surprised  at  Dr.  Ret  kalde 

memory  for  dates  and  his  familiarity  with  the  host  of  investigators  and  tl: 
special  lines  of  research,  not  only  those  in  this  country,  but  others  in  all  parts  «>f  the 
civilized  world.    This  method  of  unfolding  the  subject  historically,  with  a  final  and 
forcible  exposition  of  the  latest  current  views,  was  keenly  appreciated  by  the  stu 
and  gave  them  a  broad  and  comprehensive  picture  of  the  whole  subject,  which  was 
easily  remembered  and  understood. 

Finally,  I  must  express  my  great  regret  that  it  has  seldom  fallen 
to  my  lot  to  hear  Dr.  Reed  lecture,  and  I  have  never  witnessed  his 
demonstratioDfl  in  the  laboratory;  hence  I  have  supplemented  my 
own  remarks  by  quoting  from  others  who  had  happily  been  nmn- 
favored  in  these  respects,  and  certainly  no  statements  of  mine  could 
more  appropriately  represent  the  wmk  <>f  Pnd.  K<<d  as  a  teacher 
than  these  eloquent  expressions  from  his  own  faithful  and  loving 
pupils. 


YELLOW   FEVEE.  43 

DR.  WALTER  REED    AS    AN    AUTHOR,  BY  CH.  WARDELL  STILES,  PH.  D.,  ZOOLOGIST, 
UNITED   STATES   PUBLIC   HEALTH   AND   MARINE-HOSPITAL   SERVICE. 

Zoology  was  once  facetiously  defined  as  "The  study  of  the  useless." 
This  definition  will  doubtless  appeal  to  many  people  as  quite  appli- 
cable ;  for  to  persons  not  in  scientific  work  the  practical  application 
of  long,  detailed,  and  often  tedious  accounts  of  animals  is  not  always 
evident.  In  defending  such  work,  many  men  quote  the  time-honored 
expression  "  Knowledge  for  knowledge's  sake."  But  seeing  little 
difference  in  principle  between  this  expression  and  the  phrase  "  Money 
for  money's  sake,"  and  not  wishing  to  pose  as  a  defender  of  the 
intellectual  miser,  I  take  great  pleasure  as  a  professional  zoologist  in 
acknowledging  the  debt  which  zoology  owes  to  the  medical  profession 
for  the  practical  application  of  zoologic  knowledge  to  the  (benefit  of 
mankind. 

Zoologists  have  shown  how  important  the  insects  are  from  an 
economic  standpoint  in  making  or  destroying  certain  foods  upon 
which  we  directly  or  indirectly  depend  for  life.  But  it  is  chiefly  to 
the  medical  profession  that  this  world  is  indebted  for  the  application 
of  entomologic  knowledge  in  connection  with  the  transmission  of  the 
important  infectious  diseases,  hence  in  connection  with  saving  life. 

Dr.  Walter  Reed,  in  whose  memory  we  meet  here  this  evening, 
stands  out  among  medical  authors  as  one  who  has  been  particu- 
larly prominent  in  this  field  of  work,  and  though  he  was  not  a  zoolo- 
gist by  training,  his  writings  in  applied  zoology  in  connection  with 
yellow  fever  entitle  him  to  rank  as  among  the  greatest  of  applied 
zoologists. 

It  was  the  United  States  Bureau  of  Animal  Industry  which  first 
clearly  demonstrated  the  great  importance  of  arthropods  as  interme- 
diate hosts  of  epidemic  diseases,  and  its  reports  on  the  tick  (Boophi- 
lus)  as  a  transmitter  of  Texas  fever  of  cattle  will  always  remain  classic. 
Then  the  writings  of  two  English  physicians,  Ross  and  Manson, 
and  of  an  Italian  zoologist,  Grassi,  carried  the  subject  further  in 
connection  with  mosquitoes  and  malaria. 

Finally,  the  writings  of  our  friend  Walter  Reed  and  of  his  asso- 
ciates demonstrated  to  us  the  relation  of  mosquitoes  and  yellow 
fever  and  showed  us  how  we  could  protect  both  life  and  commerce 
from  this  scourge. 

It  is  interesting  to  note  that  all  three  of  these  discoveries  in  applied 
zoology  show  certain  parallels.  All  deal  with  diseases  which  are 
preeminently  tropical  or  subtropical;  all  deal  with  diseases  of 
unusual  economic  importance;  and  the  actual  positive  experimental 
work  upon  transmission  has  been  done  chiefly  by  English-speaking 
investigators. 

Might  I  add  here,  without  misinterpretation,  that  the  Texas  fever 
work  was  done  before  the  days  of  the  Noble  prize.  The  first  medical 
awards  of  this  prize  of  $40,000  were  to  Behring  in  recognition  of 
his  work  for  mankind  in  connection  with  diphtheria,  and  to  Pawlow 
for  his  work  in  physiology ;  the  next  award  was  to  Ross  in  recognition 
of  his  work  for  humanity  in  connection  with  malaria.  Are  not  Reed, 
Carroll,  Lazear,  and  Agramonte  the  natural  candidates  for  the  next 
award  because  of  their  work  for  mankind  in  connection  with  yellow 
fever,  and  in  case  the  conditions  of  the  grant  permit  it,  should  not 
each  of  the  widows  of  two  of  these  men  receive  the  share  which 
would  have  gone  to  her  husband  ? 


44  YELLOW  FEVER. 

DT  friend.  Dr.  Reed,  was  not  what  would  be  railed  a  prolific 

writrr.      His  numerous  routine  duties  prevented  him  from  fnrnish- 

ini:  the  manuscript  which  we  had  a  right  to  expect  from  a  man  of 

1.  beside  short  n  marks  in  society  discussions,  his 

bibEography  contains  27  original  articles  all  printed  between    iv.rj 

and    lOOl*      'Ten    of    these   articles    dealt    \\itll    Yellow    fever,    three    Mi- 
four  with  tvphoid,  tuo  eaeh  \\iih  malaria  and  erysipelas,  and  one 
with  cholera,  pneumonia,  trikresol,  vaccine,  artilicial  immunity 
agair  ination.    anurhoid    b.ulies   in    the   blood  of    vaccinated 

monkeys  and  children  and  in  variola,  formaldehyde,  snlenic  leukemia. 
and  -lie.     All  were  in  English,  and  although  they  were  all 

rnment  work,  it  is  a  striking  fact  that  onl\  >  far 

as  I  have  been  able  to  find,  wen*  pul>li>h<-d  by  the  Government. 

irarding  the  «reneral  style  of  the  articles,  there  are  three  points 
in  particular  which  are  striking:  Kir-t.  the  attenti..n  Driven  to  details 
immediately  reminds  us  of  the  writings  of  Dr.  Theobald  Smith  of 
Harvard  I  :  <m<l,  the  directness  of  diction  immediately 

reminds   us   of    Dr.   J.   McKeen   Cattell,  professor  of  experimental 
Columbia  University.     In  fact,  one  of  the  characteristics 
••.  hieh  Dr.  lie. M!  was  note<l  amonu:  his  friends  was  the  absolutely 
straight  line  of  his  thoughts  and  the  orderly,  lucid,  and  logical  devel- 
opment of  his  subject.     Third,  Dr.  Ixeed  was  of  a  judicial  teni; 
ment,  and  the  judicial  manner  in  which  he  handled  his  subject,  even 
in  controversy,  forcibly  reminds  us  of  the  same  prominent  character- 
in  Prof.  William  II.  Welch  of  Johns  Hopkins  Vnivi -r-ii 
In  forecasting  the  time  of  the  influence  of  Dr.  Reed's  writ  in^s.  it  is 
clear  that  his  articles  on  yellow  fever  will  far  outlive  his  papers  on 
other  subjects.     His  other  writings  will  be  known  to  men  only  in 
iin  lines  of  medical  work,  but  his  papers  on  yellow  fever  will  be 
known  directly  or  indirectly  to  both  physicians  and  zoologists,  and  to 
both  professional  men  and  business  men.     They  will  be  quoted  for 
decades  to  come,  both  by  Government  officials  and  by  private  practi- 
tioners, and  they  will  be  one  of  the  most  important  factors  in  deter- 
mining the  future  policy  of  civilized  nations  in  dealing  with  yellow 
fever,  a  disease  which  wre  dreaded  only  a  few  years  ago,  but  now  one 
which,  thanks  to  the  work  of  Reed  and  bis  colleagues,  will  soon  be 
little  more  than  a  medical  curiosity. 

BlIH.IOGRAPHY. 
REED,    WALTKU.      [1851-1902.] 

1892.— The  contagiousness  of  er>>  : '.MSI. in  M.  &  S.  .1  ,  \.  iL'ti  do],  M;ir<  h  in. 

p.  237. 

1893.— Remarks  on  the  cholera  spirillum.  [An  address  before  Ramsey  <'..nnty 
Medical  Society,  March  28.]  Northwest.  Lancet,  St.  Paul  (297),  v.  13  (9),  May  1, 
pp.  161-164. 

1894a. — Association  of  Proteus  vulgaris  with  Diplococcus  lanceolatus  in  a  case  of 
croupous  pneumonia.  Johns  Hopkins  Hosp.  Hull.,  Baltimore,  v.  5  (34),  March,  pp. 

_M  n 

1894b.— The  gennicidal  value  of  trikresol.  St.  Louis  M.  <fc  S.  J.  (642),  v.  66  (6), 
June,  pp.  329-337. 

1894c.—Idem.  Proc.  Am.  Mil.  Surg.  U.  S.  (Washington),  St.  Louis,  v.  4,  pp.  109- 
206. 

1894d.— A  briof  contribution  to  th«-  i(lcnti(i'-:tii..n  «,f  Stn-j.i..<-oc<-uH  erysipelatoe. 
Boston  M.  &  S  !  (14),  Octx.l.«-r  1.  pp.  339-340. 

1895a. — An  investigation  in  to  the  so-call«-<l  lymphuM  oodulea  of  the  liver  ill  typhoid 
fever.  Johns  Hopkins  Hosp.  Rep.,  Baltimore,  v.  5,  pp.  379-396. 


YELLOW   FEVEK.  45 

1895b. — An  investigation  into  the  so-called  lymphoid  nodules  of  the  liver  in  ab- 
dominal typhus.  Am.  J.  M.  Sc.,  Philadelphia,  n.  s.,  v.  110,  pp.  543-559. 

1895c. — What  credence  should  be  given  to  the  statements  of  those  who  claim  to 
furnish  vaccine  lymph  free  of  bacteria?  [Read  before  the  District  of  Columbia  Med. 
Soc.,  June  5.]  J.  Pract.  M.,  N.  Y.,  v.  5  (12),  July,  pp.  532-534. 

1896a. — [The  character,  prevalence,  and  probable  causation  of  the  malarial  fevers 
at  Washington  Barracks  and  Fort  Myer.]  Rep.  Surg.  Gen.  Army,  Wash.,  pp.  65-77, 
1  diagram,  1  table. 

1896b.— The  parasite  of  malaria.   J.  Pract.  M.,  N.  Y.,  v.  6  (9),  Apr.,  pp.  382-383. 

1897a.— Serum  diagnosis  in  typhoid  fever.  Rep.  Surg.  Gen.  Army,  Wash.,  pp. 
68-73. 

1897b. — On  the  appearance  of  certain  amoeboid  bodies  in  the  blood  of  vaccinated 
monkeys  (Rhoesus)  and  children,  and  in  the  blood  of  variola.  An  experimental  study. 
Tr.  Ass.  Am.  Physicians,  Phila.,  v.  12,  pp.  291-302,  2  pis. 

1897c. — On  the  appearance  of  certain  amoeboid  bodies  in  the  blood  of  vaccinated 
monkeys  (Rhoesus)  and  children,  and  in  the  blood  from  cases  of  variola.  An  experi- 
mental study.  J.  Exper.  M.,  N.  Y.,  y.  2  (5),  Sept.,  pp.  515-527,  pis.  38-40. 

1897d. — Typhoid  fever  in  the  District  of  Columbia;  diagnosis:  The  value  of  Widal's 
test,  the  dried  blood  method.  Nat.  M.  Rev.,  Wash.,  v.  7  (6),  Nov.,  pp.  144-146. 

1897e. — [Experiments  with  Hollister's  formaldehyde  generator.]  Rep.  Surg.  Gen. 
Army,  Wash.,  pp.  103-104. 

1898.— Splenic  leukaemia.  [Trans.  Med.  Soc.  District  of  Columbia,  Oct.  27,  1897.] 
Nat.  M.  Rev.,  Wash.,  v.  7  (9),  Feb.,  pp.  265-266. 

1900. — Report  on  the  practical  use  of  electrozone  as  a  disinfectant  in  the  city  of 
Havana,  Cuba.  Rep.  Surg.  Gen.  Army,  Wash.,  pp.  178-186.  [MS.,  dated  Apr.  20.] 

1901a. — The  propagation  of  yellow  fever;  observations  based  on  recent  researches. 
[Address before  103d  Ann.  Meeting  Med.  andChir.  Fac.,  State  of  Md.,  Bait.,  Ap.  24-27.] 
Med.  Rec.,  N.  Y.  (1605),  v.  60  (6),  Aug.  10,  pp.  201-209,  tables  1,  2. 

1901b.— Idem.     Rep.  Surg.  Gen.  Army,  Wash.,  pp.  187-202,  1  pi.,  6  fever  charts. 

1902. — Recent  researches  concerning  the  etiology,  propagation,  and  prevention  of 
yellow  fever,  by  the  United  States  Army  Commission.  J.  Hyg.,  Cambridge,  Eng., 
v.  2  (2),  Apr.  1,  pp.  101-119,  charts  1-3. 

REED,   WALTER,    AND    CARROLL,    JAMES. 

1899a. — Bacillus  icteroides  and  Bacillus  cholerae  suis.  A  preliminary  note.  Med. 
News,  N.  Y.,  v.  74  (17),  Apr.  29,  pp.  513-514. 

1899b. — The  specific  cause  of  yellow  fever.  A  reply  to  Dr.  G.  Sanarelli.  Med. 
News,  N.  Y.,  v.  75  (11),  Sept.  9,  pp.  321-329. 

1900. — A  comparative  study  of  the  biological  characters  and  pathogenesis  of  Bacillus 
X  (Sternberg),  Bacillus  icteroides  (Sanarelli),  and  the  hog-cholera  bacillus  (Salmon 
and  Smith).  [Received  for  publication  Feb.  25.]  J.  Exper.  M.  [Bait.],  v.  5  (3), 
Dec.  15,  pp.  215-270,  figs,  a-o,  pi.  19,  figs.  1-3. 

1901. — The  prevention  of  yellow  fever.  [Read  at  29th  Ann.  Meeting,  Am.  Pub. 
Health  Ass.,  Buffalo,  Sept.  16-21.]  Med.  Rec.,  N.  Y.  (1616),  v.  60  (17),  Oct.  26, 
pp.  641-649,  figs.  1-10. 

1902.— The  etiology  of  yellow  fever.  A  supplemental  note.  [Read  at  3d  Ann. 
Meeting,  Soc.  Am.  Bacteriologists,  Chicago,  Dec.  31,  1901,  and  Jan.  1,  1902.]  Am. 
Med.,  Phila.,  v.  3  (8),  Feb.  22,  pp.  301-305,  charts  1-6. 

REED,  WALTER;  CARROLL,  JAMES;  AND  AGRAMONTE,  ARISTIDES. 

1901a. — The  etiology  of  yellow  fever.  An  additional  note.  [Read  at  Pan-Am.  Med. 
Cong.,  Havana,  Cuba,  Feb.  4-7.]  J.  Am.  Med.  Ass.,  Chicago,  v.  36  (7),  Feb.  16, 
pp.  431-440,  charts  1-6. 

1901b.— Experimental  yellow  fever.  Am.  Med.,  Phila.,  v.  2  (1),  July  6,  pp.  15-23, 
charts  1-8,  tables  1-2. 

REED,  WALTER;  CARROLL,  JAMES;  AGRAMONTE,  ARISTIDES;  AND  LAZEAR,  JESSE  w. 

1900.— The  etiology  of  yellow  fever.  A  preliminary  note.  [Read  at  Meeting  of 
Am.  Pub.  Health  Ass.,  Indianapolis,  Ind.,  Oct.  22-26.]  Phila.  M.  J.  (148),  v.  6  (17), 
Oct.  27,  pp.  790-796,  tables  1-3,  charts  1-2. 

REED,  WALTER,  AND  STERNBERG,  GEORGE  M. 

1895. — Report  of  immunity  against  vaccination  conferred  upon  the  monkey  by  the 
use  of  the  serum  of  the  vaccinated  calf  and  monkey.  Tr.  Ass.  Am.  Physicians,  Phila., 
v.  10,  pp.  57-69. 


46  YELLOW   FEVER. 

DR.  REED'S  WORK  IN  CUBA,  BY  MAJ.  GEN.  LEONARD  WOOD,  UNITED  STATES  ARMY. 

[Abttnot] 

The  work  of  Dr.  Walter  Reed  is  the  most  important  work  in  tho 
way  of  medical  research  and  discovery  which  has  been  accomplished 
by  any  one  who  has  lived  in  this  hemisphere.  There  is  no  other 
medical  discovery  to  which  it  can  he  compared,  unless  it  be  that  of 
anesthesia.  The  results  to  humanity  are  incalculable  and  fai  reach- 
ing. It  is  safe  to  say  that  this  discovery  has  resulted  in  saving  each 
year  more  lives  than  were  lost  in  the  war  with  Spain,  and  in  a  saving 
to  commerce,  and  especially  to  the  southern  portion  of  our  count rv. 
of  an  amount  equal  to  the  cost  of  the  war  with  Spain. 

The  following  letters  and  telegrams  were  received: 

WASHINGTON,  D.  C.,  December  29, 1902. 
Dr.  S.  S.  ADAMS, 

President  District  Medical  Society. 
MY  DEAR  DR.  ADAMS:  I  regret  exceedingly  that  an  engagement  made  some  time 

and  from  which  I  can  not  excuse  myself,  will  prevent  me  from  att« 
Reed  memorial  meeting  on  Wednesday  evening. 

No  one  appreciates  more  deeply  than  I  do  the  loss  to  scientific  medicine  and  to  the 
medical  corps  of  the  army  caused  by  Maj.  Reed's  death.    His  scientific  work  was 
eminently  fruitful  and  far-reaching  in  its  results.    As  the  head  of  the  medical  corps 
during  nine  years  of  his  most  useful  work,  which  was  prosecuted  under  my  g< 
direction,  I  am  of  course  entirely  familiar  with  the  results  accomplish 

Maj.  Reed  was  endowed  by  nature  and  bv  training  with  the  essential  qualiti* 
for  engaging  in  research  work  in  the  special  field  to  which  he  devoted  his  tal<  r: 
his  energies.    Conservative,  painstaking,  thorough,  persevering,  and  ready  in  ro«< 
he  acquitted  himself  with  credit  in  every  task  assigned  to  him,  and  "ha- 
great  and  deserved  distinction  by  his  successful  demonstration  of  the  method  by  which 
yellow  fever  is  transmitted  from  man  to  man.     In  addition  to  this,  he  was  a  modest 
and  courteous  gentleman,  who  attracted  all  of  those  who  came  in  contact  with  him. 
His  death  came  to  me,  as  to  his  other  numerous  friends,  as  a  great  persona  1 
irreparable  loss. 

Very  truly,  yours,  GEO.  M.  STERNBERG. 

BALTIMORE,  December  30,  190f. 

DEAR  DR.  ADAMS:  I  have  to  leave  unexpectedly  to-day   for  Canada.    Please 
express  my  regrets  that  I  can  not  be  at  the  memorial  meeting  to  Reed. 
With  kind  regards,  sincerely  yours, 

WM.  OSLER. 


RICHMOND,  VA.,  December  SI,  190f . 
Maj.  J.  R.  KEAN, 

Surgeon  General's  Office,  War  Department,  Washington,  D.  C.: 
Greatly  regret  I  can  not  attend  the  meeting  to-night  in  honor  of  Dr.  Hood,  whose 
friendship  I  prized,  whose  character  I  admired,  and  whose  contribution  to  science  and 
country  can  not  be  measured. 

HUGH  LEE. 


TREASURY  DEPARTMEN 
PUBLIC  HEALTH  AND  MARINE-HOSPIT  ICE, 

Washington,  D.  C.,   January  5,  1903. 
Dr.  F.  S.  NABH, 

17t3  Q  Street,  Washington,  D.  C. 

MY  DEAR  DR.  NABH:  As  you  may  know  by  this  time,  I  have  been  absent  from  the 
city  for  a  month  and  returned  Saturday.  On  opening  my  mail  to-day  I  find  your 
note  of  December  9,  and  I  wish  to  express  my  great  regret  that  I  could  not  have  been 
here  to  accept  the  honor  which  was  conferred  upon  me  of  responding  at  a  meeting 
held  in  memory  of  Dr.  Reed .  It  would  have  been  a  great  privilege  to  have  taken  pan 


YELLOW   FEVER.  47 

in  that  meeting,  and  of  all  the  things  which  I  have  missed  by  being  away  one  month 
I  regret  this  more  than  any  other. 

I  had,  during  his  life,  the  highest  regard  for  Dr.  Reed  as  a  scientist,  and,  more  than 
that,  I  had  the  warmest  feeling  of  frienship  toward  him,  although  we  were  by  no  means 
intimate,  and  certinly  his  death  was  a  blow  to  science  and  the  whole  governmental 
service. 

I  had  a  conviction  that  in  the  near  future  the  service  of  which  I  have  charge  would 
find  a  way  of  having  some  official  connection  with  Dr.  Reed  in  his  great  work,  and  that 
through  him  the  bond  of  union  between  the  medical  services  of  the  Government 
would  be  materially  strengthened. 

I  have  learned  that  Dr.  Stiles  took  the  place  which  was  intended  for  myself,  and 
I  am  much  gratified  that  he  did. 
Very  sincerely  yours, 

WALTER  WYMAN. 


CHAI-TK.K  6. 

VALUE  OF  DR.  REED'S  WORK  AND  EXPRESSION  OF  APPRE- 
CIATION.' 

Popular  appreciation  of  the  value  of  the  work  of  the  Yellow  Fever 
Commission  has  been  singularly  alow  and  impeilVrt.  While  nearlv 
y  educated  person  in  the  United  States  is  lamiliar  with  the  name 
and  \\cik  of  a  distinguished  Austrian  surgeon  who  has  recently 
demonstrated  in  this  country  an  operation  for  the  cure  of  a  rather 
rare  deformity  in  children,  only  a  small  fraction  of  them  knew  any- 
thing of  Walter  Reed,  the  conqueror  of  i  low  pL  And 
yet  distinguished  men  have  not  been  silent  in  regard  to  him.  < 
Leonard  Wood  said,  in  a  recent  address  at  a  memorial  meeting  of 
scientific  men  held  in  honor  of  his  memory  in  Washington: 

I  know  of  no  other  man  on  this  side  of  the  world  who  has  done  so  mucli  fur  Immunity 
as  Dr.  Reed.     His  discovery  results  in  the  saving  of  more  lives  annually  than 
lost  in  the  Cuban  war,  and  saves  the  commercial  interests  of  the  world  a  greater 
financial  loss  each  year  than  the  cost  of  the  Cuban  war.    He  came  to  Cuba  at  ;. 
when  one-third  of  the  officers  of  my  staff  died  of  yellow  fever,  and  we  were  dis- 
couraged at  the  failure  of  our  efforts  to  control  the  disease.     In  th«»  m< 
the  disease  was  ordinarily  worst  the  disease  was  checked  and  driven  ir -in  II 
That  was  the  first  time  in  nearly  200  years  that  the  city  had  been  rid  «'f  it.     The 
value  of  his  discovery  can  not  be  appreciated  by  persons  who  are  not  familiar  with 
the  conditions  of  tropical  countries.     Hereafter  it  will  never  be  possible  for  yellow 
fever  to  gain  such  headway  that  quarantine  will  exist  from  the  mouth  of  the  Poto- 
mac to  the  mouth  of  the  Rio  Grande.     Future  generations  will  appreciate  fully  tin- 
value  of  Dr.  Reed's  services.     His  was  the  originating,  diroctinir.  and  controlling 
mind  in  this  work,  and  the  others  were  assistants  only. 

In  a  letter  dated  November  24  General  Wood  said : 

To  Maj.  Reed  belongs  the  honor  of  having  led  in  the  greatest  medical  work  of  modern 
times,  and  the  results  he  accomplished  will  live  for  all  time. 

Prof.  William  H.  Welch,  of  Johns  Hopkins,  said  in  a  letter  to  the 
Secretary  of  War: 

Dr.  Reed's  researches  in  yellow  fever  are  by  far  the  most  important  contributions 
to  science  which  have  ever  come  from  an  Army  surgeon.     In  my  judgment,  th< 
the  most  valuable  contributions  to  medicine  and  public  hygiene  which  have 
been  made  in  this  country  with  the  exception  of  the  discovery  of  anaesthesia.     1 
have  led  and  will  lead  to  the  saving  of  untold  thousands  of  lives.  I  am  in  a  p<> 
to  know  that  the  credit  for  the  original  ideas  embodied  in  this  work  belongs  wholly 
to  Maj.  Reed.    Such  work,  if  done  in  Europe,  would  receive  substantial  recopi 
from  the  Government. 

He  was  last  year  given  the  degree  of  LL.  D.  bv  the  University  of 

Michigan,  and  the  degree  of  M.  A.  by  Harvard  University.      In  ('-nn- 
f erring,  the  language  used  by  President  Eliot  was: 

Walter  Heed,  graduate  of  medicine  of  the  University  of  Virginia,  the  Army  surgeon 
who  planned  and  dirc<  ted  in  Cuba  the  experiments  which  have  given  man  control 
over  that  fearful  scourge,  yellow  fo\ 

i  "The  scientific  work  and  discoveries  of  the  late  Maj.  Walter  Reed.  '  s  Array"  (8.  Doc. 

Mo.  11B,  Jan.  28, 1003),  ordered  to  be  published.    Prepared  by  Maj.  Jefferson  K.  Kean. 

48 


YELLOW   FEVEE.  49 

Precedents  are  abundant  for  State  aid  to  public  benefactors  and 
their  families.  The  English  Government  a  century  ago,  when  the 
purchasing  value  of  money  was  far  greater  than  at  present,  gave  to 
Jenner,  the  discoverer  of  vaccination,  grants  amounting  to  £30,000. 
He  also  received  £7,383  from  a  subscription  in  India. 

Pasteur,  the  founder  of  the  science  of  bacteriology,  besides  numer- 
ous honors  and  decorations  and  money  donations  from  other  sources, 
received  from  the  French  Government  a  pension  of  12,000  francs. 

Lister,  the  originator  of  antiseptic  surgery,  has,  besides  numerous 
honors  and  decorations,  been  successively  knighted  and  elevated  to 
the  peerage. 

In  this  country  a  bill  to  donate  $100,000  to  the  discoverer  of  anaes- 
thesia was  twice  passed  by  the  Senate  (in  1853  and  1854),  but  failed 
in  the  House,  probably  because  of  the  uncertainty  as  to  which  of  the 
rival  claimants  was  entitled  to  the  credit  of  that  discovery. 

The  resolutions  of  various  scientific  and  professional  societies  are 
appended  as  an  indication  of  the  standing  which  Dr.  Reed  occupied  in 
the  scientific  world  at  the  time  of  his  death. 

The  following  editorial  from  a  prominent  medical  journal,  American 
Medicine,  is  also  quoted  on  account  of  its  pertinence  to  the  question: 

DUE    REWARDS   FOR    SCIENTIFIC   ACHIEVEMENTS. 

The  recent  death  of  Maj.  Walter  Reed  directs  attention  to  the  self-sacrifice  of  the 
medical  investigator  and  the  inadequacy  of  the  recognition  which  is  attainable  in 
America  by  these  heroes  of  science.  His  demise  deprives  the  country  of  a  citizen 
whose  public  spirit,  devotion  to  duty,  and  splendid  achievements  justly  entitle  him 
to  an  enduring  testimonial.  His  scientific  career,  strictly  speaking,  began  about 
1890,  when,  through  the  stimulating  influence  of  his  illustrious  teacher,  Dr.  Welch, 
of  Johns  Hopkins,  his  interest  was  awakened  in  the  intimate  nature  and  underlying 
causes  of  disease,  and  he  took  up  the  special  study  of  pathology  and  bacteriology. 
With  rare  native  intelligence,  indefatigable  industry,  high  ideals,  broad  sympathies, 
and  a  personality  that  attracted  all  who  came  in  contact  with  him,  he  soon  distin- 
guished himself  as  a  trustworthy,  independent  investigator,  and  entered  upon  a  work 
that  was  to  become  a  triumph  for  scientific  medicine  and  a  blessing  to  humanity. 
Notwithstanding  his  manifold  duties  as  curator  of  the  Army  Medical  Museum,  Reed 
never  lost  his  love  for  pure  medical  investigation,  and  was  a  frequent  contributor  to 
medical  literature.  Yet  while  his  contributions  in  general  to  scientific  medicine  are 
uniformly  as  good  as  the  best,  they  are  insignificant  when  compared  with  the  great 
work  upon  yellow  fever  with  which  his  name  will  ever  be  inseparably  associated. 
His  was  the  master  mind  and  he  the  guiding  spirit  in  an  investigation  whereby  mul- 
titudes of  lives  have  been  saved,  a  pestilential  malady  robbed  of  its  mysteries  and 
terrors,  and  an  annual  expenditure  of  millions  of  money  shown  to  be  in  large  part, 
if  not  entirely,  needless.  As  has  been  said,  his  work  "means  to  the  United  States  for 
the  future  a  saving  in  life  and  treasure  that  is  cheaply  paid  for  by  the  whole  cost  of 
the  Spanish- American  War." 

In  other  countries  a  man  who  had  done  such  a  work  as  Reed  would  at  once  receive 
office,  honors,  and  financially  security.  In  ours  we  leave  him  unrewarded,  to  work 
out  his  life,  to  die  early,  perhaps,  and  then  we  offer  his  family  a  sum  as  a  pension 
small  beyond  ridicule.  We  appeal  to  Congress  to  demonstrate  the  nation's  gratitude 
in  this  case.  It  should  act  promptly  and  in  a  manner  commensurate  with  the  mag- 
nificient  public  service  rendered  by  our  colleague.  This,  we  are  sure,  is  the  wish  of 
everyone  conversant  with  what  he  has  done. 

RESOLUTIONS  OF  MEDICAL  SOCIETIES  AND  LEARNED  BODIES  WITH  REF- 
ERENCE TO  MAJ.  WALTER   REED,  SURGEON,  UNITED  STATES  ARMY. 

At  a  stated  meeting  of  the  New  York  Academy  of  Medicine,  held 
December  3,  1902,  the  following  resolution  was  unanimously  adopted: 

Whereas  in  the  recent  death  of  Dr.  Walter  Reed,  major  and  surgeon,  United  States 
Army,  the  science  of  medicine  has  lost  the  one  whose  brilliant  research  led  first  to  the 

79965°— S.  Doc.  822,  61-3 4 


50  VER. 

demonstration  of  the  transmission  of  yellow  fever  by  the  mosquito,  and  later  to  the 
practical  removal  of  the  disease  from  a  large  part  of  Cuba  and  the  prevention  of  its 
transmission  to  the  shores  of  this  country:  Be  it 

Resolved,  That  the  New  York  Academy  of  Medicine  records  its  sens,  of  the  -ivat- 
ness  of  the  loss  to  science  and  to  mankind  and  its  sympathy  with  the  friends  and 
relatives  of  the  deceased. 

The  following  minutes  and  resolutions  were  adopted  at  a  special 
meeting  of  the  faculty  of  the  medical  department  of  the  Columbian 
University: 

The  sudden  and  unexpected  demise  of  our  .-t.-.-m.-d  friend  and  colleague.  Maj. 
Walter  Reed,  United  States  Army,  professor  of  -y  and  pathology  in  the 

medical  school  of  the  Columbian  University,  is  an  event  that  brings  to  us  the  most 
acute  regret  and  overwhelming  sorrow. 

Taken  from  us  in  the  prime  of  manhood  and  in  the  /.enith  of  his  professional  use- 
fulness, at  a  time  when  the  medical  profession  and  humanity  at  larp< 
to  do  him  homage  for  his  great  work  in  demonstrating  the  method  of « -x terminating 
yellow  fever  by  pr  rom  inoculating  mosquitoes  and  by  whi<  h  thai 

disease  has  been  abolished  from  some  of  its  most  malignant  haunts— at  a  tin.. 
when  his  relations  with  the  faculty  and  students  of  the  Columbian  Ini 
become  securely  united  by  bonds  of  mutual  affection  and  esteem — under  th« 
cumstances  it  is  with  a  most  earnest  and  sincere  feeling  that  we,  t  h«-  me -di« -al  faculty 
of  the  Columbian  University,  hereby  desire  to  express  our  unreserved  admiration  for 
the  work,  life,  and  character  of  Prof.  Reed,  both  as  a  physician,  a  te;. 
friend,  and  a  man  of  science.     In  testimony  whereof,  it  is  hereby 

Resolved,  That  the  foregoing  note  be  recorded  in  the  permanent  archives  of  the 
faculty;  that  a  copy  of  the  same  be  given  to  the  press  for  publication  and  also  for- 
warded to  the  family  of  Dr.  Reed  as  an  evidence  of  our  sympathy  for  thorn  in  th«-ir 
great  sorrow. 

Resolved,  That,  as  a  further  mark  of  respect  for  our  lamented  colleague,  the  exercises 
of  the  medical  school  be  suspended  ana  that  the  students  and  faculty  attend  in  a 
body  his  funeral  obsequies. 

The  following  resolutions  were  adopted  by  the  medical  faculty  of 
the  University  of  Virginia  December  8,  1902,  and  by  them  reported  to 
the  general  faculty,  which  heartily  concurred  in  this  expression  ,,f 
regard  for  the  memory  of  Dr.  Reed,  of  admiration  for  his  work 
of  sympathy  for  his  family : 

The  medical  faculty  of  the  University  of  Virginia  have  heard  with  deep  sorrow 
of  the  death  of  Maj.  Walter  Reed,  professor  of  bacteriology  and  pathology  in  the 
Army  Medical  School,  and  distinguished  graduate  of  Jrttis  medical  depart  in 

His  masterly  investigation  of  the  causes  of  the  outbreaks  of  typhoid  f«-\cr  in  the 
United  States  Army  auring  the  Spanish-American  War,  and  especially  his  work 
furnishing  conclusive  proof  of  the  conveyance  of  yellow  fever  by  the  mosquito,  entitle 
him  to  a  preeminent  place  amongst  scientists  and  sanitarians  and  will  prov< 
mable  service  to  mankind. 

As  an  alumnus  he  was  true  and  loyal,  manifesting  on  every  appropriate  occasion 
his  continued  interest  in  the  university,  upon  which  he  had  reflected  great  <  n dit 

In  testimony  of  our  high  appreciation  of  his  character  and  achievements  it  is  hereby 

Resolved,  That  the  foregoing  note  be  spread  upon  our  minutes  and  a  copy  L- 
warded  to  the  family  of  Dr.  Reed  as  an  evidence  of  our  sympathy  for  them  in  their 
great  sorrow. 

RESOLUTIONS   OF  THE   AMERICAN    ASSOCIATION   FOR  THE   ADVANCEMENT   OF   SCIENCE. 

Resolved.  That  the  American  Association  for  the  Advancement  of  .,  reby 

records  its  sense  of  the  great  loss  sustained  by  8eicn«>  in  th<-  d< 
Reed,  surgeon  in  the  United  States  Army,  and  its  appreciation  of  th«    f  ir  r< : 
and  invaluable  services  which  he  has  rendered  to  humanity.     By  solving  th«  problem 
of  the  mode  of  spread  of  yellow  fever,  Mai.  Reed  not  only  made  a  great  contribution 
to  science,  but  at  the  same  time  conferred  inestimable  benefits  upon  his  country  and 
upon  mankind.    To  have  discovered  and  demonstrated  the  methods,  which  have 
already  been  successfully  tested  in  Cuba,  of  eradicating  a  widespread  and  t<  rrihlo 
pestilence,  is  a  benefaction  of  imperishable  renown,  of  incalculable  value  in  the  sav- 
ing of  human  lives,  of  vast  importance  to  commercial  interests,  and  deserving  the 


YELLOW   FEVER.  51 

highest  rewards  in  the  power  of  his  countrymen  to  bestow.  This  association  earn- 
estly urges  upon  the  attention  of  Congress  the  duty  of  making  full  provision  for  the 
support  of  his  family. 

Resolved,  That  the  president  designate  a  committee  of  nine  members  of  this  associa- 
tion, with  power  to  increase  its  number,  which  shall  be  authorized  and  requested  to 
devise  and  carry  out  a  plan  or  aid  in  similar  efforts  elsewhere  instituted,  by  which 
a  suitable  and  permanent  memorial  of  this  great  benefactor  of  his  race  may  be  secured. 
This  committee  shall  be  authorized  to  prepare  and  publish  a  statement  of  the  services 
of  the  late  Maj.  Reed  in  discovering  the  mode  by  which  yellow  fever  may  be  exter- 
minated. 

The  following  resolution  was  adopted  at  the  meeting  of  the  Ameri- 
can Medical  Association  at  Saratoga,  N.  Y.,  on  June  11,  1902: 

Whereas  the  members  of  the  American  Medical  Association  believe  that  the  recent 
work  of  the  United  States  Army  surgeons  in  Cuba  in  relation  to  the  discovery  of  the 
method  of  transmission  of  yellow  fever  is  of  such  magnitude  and  far-reaching  benefi- 
cence as  to  rank  only  second  with  Tenner's  discovery  of  vaccination;  and 

Whereas  the  practical  value  of  this  discovery  has  been  proven  by  the  complete 
eradication  of  this  scourge  from  Habana: 

Resolved,  That  the  thanks  of  this  association  be  tendered  the  gentlemen  who 
accomplished  this  brilliant  result,  and  particularly  to  Drs.  Walter  Reed,  James  Car- 
roll, A.  Agramonte,  W.  O.  Gorgas,  and  to  Leonard  Wood,  who  recognized  the  impor- 
tance of  the  work  and  made  it  possible  by  his  hearty  encouragement  and  assistance. 

Resolved,  That  this  association,  while  deeply  deploring  the  death  of  Dr.  Jesse  A. 
Lazear,  who  died  a  martyr  to  science,  admires  and  gratefully  acknowledges  the  heroic 
devotion  of  this  physician  and  some  of  the  members  of  the  Hospital  Corps  to  the  cause 
of  humanity. 

Resolved,  That  these  resolutions  be  published  in  The  Journal,  and  that  copies  be 
transmitted  to  Drs.  Reed,  Carroll,  Agramonte,  Wood,  Gorgas,  and  Mrs.  Lazear. 

RESOLUTIONS  TAKEN  BY  THE  INTERNATIONAL  CONGRESS  OF  MEDICINE  AT  CAIRO,  EGYPT, 

DECEMBER   22,    1902. 

Les  membres  du  Premier  Congres  de  Medecine  en  Egypte  apprennant  avec  le  plus 
profond  regret  la  mort  prematuree  du  Maj.  Walter  Reed  du  Corps  Medical  de  1'Armee 
des  Etats  Unis  d'Amerique. 

La  part  brillante  et  importante  qu'il  a  pris  dans  la  decouverte  du  moustique 
8te"gomyia  comme  le  seul  agent  transmitteur  du  parasite  de  la  fievre  jaune,  reussessant 
ainsi  a  mettre  les  ravages  de  cette  terrible  maladie  sous  le  controle  des  hygienistes 
fait  de  sa  mort  une  perte  cruelle  pour  I'humamte. 

Le  Congres  decide  en  consequence  d'exprimer  a  cette  occasion  toute  sa  sympathie 
au  Corps  Medical  de  1'Armee  des  Etats  Unis  ainsi  qu'a  la  famille  du  Maj.  Reed. 

Le  Congres  decide  en  outre  de  prier  le  secretaire  du  Cpngres  d'envoyer  officielle- 
ment  par  1'entremise  des  Autorites  competentes  une  copie  de  la  presente  resolution 
au  Chirurgien  en  Chef  de  PArme'e  des  Etat  Unis  d'Amerique  et  une  autre  egalment 
a  Madame  Veuve  Reed. 

[From  an  editorial  in  American  Medicine  (referring  to  Maj.  Reed).] 

His  was  the  master  mind  and  he  the  guiding  spirit  in  an  investigation  whereby 
multitudes  of  lives  have  been  saved,  a  pestilential  malady  robbed  of  its  mysteries 
and  terrors,  and  an  annual  expenditure  of  millions  of  money  shown  to  be  in  large 
part,  if  not  entirely,  needless. 

[From  the  resolutions  of  the  American  Association  for  the  Advancement  of  Science.] 

By  solving  the  problem  of  the  mode  of  spread  of  yellow  fever  Maj.  Reed  not  only 
made  a  great  contribution  to  science,  but  at  the  same  time  conferred  inestimable 
benefits  upon  his  country  and  upon  mankind.  To  have  discovered  and  demonstrated 
the  methods,  which  have  already  been  successfully  tested  in  Cuba,  of  eradicating  a 
widespread  and  terrible  pestilence  is  a  benefaction  of  imperishable  renown,  of  incal- 
culable value  in  the  saving  of  human  lives,  of  vast  importance  to  commercial  interests, 
and  deserving  the  highest  rewards  in  the  power  of  his  countrymen  to  bestow. 

[From  lecture  of  Sir  Patrick  Manson,  M.  D.,  medical  adviser  of  the  British  Colonial  Office.] 

—Dr.  Walter  Reed  did  a  great  and  beneficent  work.  We  in  England  thoroughly 
appreciate  this,  and  heartily  sympathize  with  America  in  the  loss  she  and  the  world 


52  YRLLOW   FEVEB. 

has  sustained  by  his  premature  death.    The  beet  tribute  we  can  pay  to  hi*  mcmor 
once  to  apply  liia  discovery.    Let  us  hope  that  the  good  he  has  done  will  i. 
interred  with  his  bones,  and  that  his  countrymen  and  t|u>  n-t  of  us  will  i 
push  forward  the  great  and  beneficent  measures  hi*  brilliant  labors  so  clearly  iiui 

Similar  resolutions  have  been  passed  by  numerous  other  scientific 
bodies.  They  arc  not  given  here  because  it  is  not  desired  unduly  to 
lengthen  this" report. 

INCORPORATORS  OP  "THE  WALTER  REED  MEMORIAL  ASSOCIATION, "  WASHINGTON,  D.  C. 

R.  M.  O'Reillv,  Surgeon  General .  tinted  States  Army.  Washington,  D.  C. 

P.  V  Surgeon  General,  United  States  Navy,  Washington,  D.  C. 

Wa !  I , .  D . ,  Surgeon  General,  United  States  Public  Health  and  Ma  r  i  n .  • 

Hospital  Service,  Washington,  D.  C. 

George  M.  Steinberg,  LL.  D.,  brigadier  general,  United  States  Army 
Washington,  D 

Calvin  Do  Witt,  brigadier  general,  United  States  Army  (retired),  Washington,  D.  C. 

Dan i-l  0,  oilman,  LL.  D.,  president  of  Carnegie  Institution.  Washington,  D.  C. 

ilium.  I.L.  D.,  president  of  Columbian  tni\  D.  C. 

Carroll  D.  Wright,  LL.  D.,  Commissioner  of  Labor,  Washington,  D 

ry  B.  F.  Mac  far  land,  president  Board  of  Commissioners,  District  of  Columbia. 

!1  St.  George  Turk*  r.  LI..  D.,  dean  of  school  of  law  and  diplomacy,  Columbian 
University,  Washington,  D.  C. 

Alexander  Graham  Bell,  LL.  D.,  Columbian  University,  Washington,  D.  C. 

G.  Wrythe  Cook,  M.  D.,  LL.  D.,  Washington,  D.  C. 

A.  F.  A.  King,  M.  D.,  dean  emeritus  medical  school,  Columbian  University,  Wash- 
ington, D.  C. 

Chas.  Wardell  Styles,  M.  D.,  Chief  of  Division  of  Zoology,  Hygienic  Laboratory, 
United  States  Public  Health  and  Marine-Hospital  Service,  Washington,  D.  C. 

W.  J.  Boardman,  Washington,  D.  C. 

William  A.  Gordon,  lawyer,  Washington,  D.  C. 

Maj.  J.  R.  Kean.  surgeon,  t'nit<-<l  States  Army,  War  Department,  Washington,  D.  C. 

Maj.  W.  D.  McCaw,  surgeon,  United  States  Army,  War  Depar  tshington, 

D.  O. 

Capt.  C.  R.  Darnall,  assistant  surgeon,  United  States  Army,  W;i  rnent, 

Washington,  D.  C. 

First  Lieut.  Jas.  Carroll,  assistant  surgeon,  United  States  Army,  War  Department, 
Washington,  D.  C. 

-.Nash,  M.  D.,  Washington,  D.  C. 


WALTER  REED   (SCHULER.. 


PART  II —THE  PUBLICATIONS  OF  WALTER  REED  AND  HIS  ASSOCIATES 
ON  THE  COMMISSION  IN  REGARD  TO  YELLOW  FEVER, 


CHAPTER  1. 

BACILLUS    ICTEROIDES    AND     BACILLUS    CHOLER33     SUIS— A 
PRELIMINARY  NOTE. 

By  WALTER  REED,  M.  D.,  Surgeon,  United  States  Army,  and  JAMES  CARROLL,  M.  D., 
Acting  Assistant  Surgeon,  United  States  Army. 

[Reprinted  from  the  Medical  News,  April  29,  1899.] 

In  the  course  of  a  comparative  study  of  Bacillus  x  (Sternberg)  and 
Bacillus  icier oides  (Sanarelli)  which  has  engaged  our  attention  as 
opportunity  would  permit  during  the  past  18  months,  we  have  had 
occasion  to  observe  the  effect  produced  by  the  intravenous  injection 
in  dogs  of  other  micro-organisms,  such  as  the  Bacillus  coli  communis 
and  the  Bacillus  cholerse  suis.  Without  entering  into  details  in  this 
preliminary  note  we  may  state  that  the  same  clinical  symptoms, 
viz,  vomiting,  increased  action  of  the  bowels,  and  profound  prostra- 
tion, which  are  produced  in  dogs  by  the  intravenous  injection  of  B. 
icteroides,  are  also  brought  about  by  a  like  inoculation  of  the  hog- 
cholera  bacillus.  When  death  occurs,  the  stomach  contains  a  con- 
siderable quantity  of  fluid  blood  and  extensive  hemorrhagic  lesions 
are  present  in  the  small  intestine.  We  have  not  found  fatty  degenera- 
tion of  the  liver,  since  our  dogs,  few  in  number,  injected  with  the  hog- 
cholera  bacillus,  have  died  too  early  for  this  change  to  occur.  We 
have  also  failed  to  discover  any  fatty  degeneration  in  the  liver  of  dogs 
that  have  died  within  a  few  days  after  the  intravenous  injection  of 
B.  icteroides.  This  change  has  only  been  met  with  in  two  instances, 
when  the  animals  had  survived  until  the  ninth  day  after  inoculation 
with  B.  icteroides.  In  neither  of  these  cases,  however,  was  the  degree 
of  fatty  degeneration  at  all  comparable  with  that  present  in  the 
human  liver  in  yellow  fever. 

In  addition  to  the  experiments  upon  dogs,  we  have  compared  the 
course  of  the  infection  and  the  lesions  produced  in  guinea  pigs  and 
rabbits  inoculated  with  small  quantities  of  B.  icteroides  and  B.  cholerse 
suis,  and  have  been  much  impressed  with  the  similarity  of  the  results 
obtained.  The  same  cyclical  course  of  the  infection  described  by 
Sanarelli  for  guinea  pigs  inoculated  with  B.  icteroides  is  seen  in  these 
animals  when  injected  with  like  quantities  of  B.  cholerse  suis.  The 
greater  susceptibility  and  shorter  course  of  the  infection  in  rabbits 
applies  equally  to  both  micro-organisms.  Theobald  Smith  has  called 
attention  to  the  extreme  susceptibility  of  these  animals  to  inoculation 
with  minute  quantities  of  the  hog-cholera  bacillus.1  We  have  suc- 

i  Bulletin  No.  6,  U.  S.  Department  of  Agriculture,  1894. 

53 


CHAPTER  2. 

THE  ETIOLOGY  OF  YELLOW  FEVER— A  PRELIMINARY  NOTE.1 

By  WALTER  REED,  M.  D.,  Suryoon,  I Hit.-d  States  Army,  JAMES  CARROLL,  M    I>  : 
VORAMOXTB,  M.  D.,  and  JESSE  W.  LAZEAR,  M.  D.,1  Acting  Assistant  Surgeon, 
United  States  Army. 

The  writer-.  c<>nM  inning  a  board  of  medical  officers  convened  ''for 
the  purpose  or  pursuing  scientific  investigations  with  n-fViviu •<>  t«>  the 
acute  infectious  diseases  prevalent  on  the  Island  of  Cul>;i."  arrived 
at  our  station,  Columbia  Barracks,  Quemados,  Cuba,  on  June  25  of 
the  present  year,  and  proceeded,  under  written  instructions  from  the 
Surgeon  General  of  the  Army.  t«>  "gjve  special  attention  to  questions 
relatini:  to  the  etiology  and  prevention  of  yellow  fe\ 

TWO  Of  its  members  (Airnimnnte  :md  L&zear)  were  stationed  on  the 
Island  of  Cuba,  the  former  in  Habana,  and  the  latter  at  Columbia 
Barracks,  and  were  already  pursuing  investigations  relating  to  the4 
etiology  of  this  disease. 

Fortunately  for  the  purposes  of  this  board,  an  epidemic  <>f  yellow 
fever  was  prevailing  in  the  adjacent  town  of  Quemados,  Cuba,  at  the 
time  of  our  arrival,  thus  furnishing  us  an  opportunity  I'm-   <li 
observations  and  for  bacteriological  and  pathological  work.     The 
results  already  obtained,  we  believe,  warrant  the  publication  at  this 
t  ime  of  a  preliminary  note.     A  more  detailed  account  of  our  obs< 
tions  will  be  submitted  to  Surgeon  General  Sternberg  in  a  future 
report. 

The  first  part  of  this  preliminary  note  will  deal  with  the  result 
blood  cultures  during  life  and  of  cultures  taken  from  yellow  I 
cadavers,  reserving   for   the   second    part    a   consideration    of    the 
mosquito  as  instrumental  in  the  propagation  of  yellow  fever,  with 
observations  based  on  the  biting  of  nonimmune  human  beings  by 
mosquitoes  which  had  fed  on  patients  sick  with  yellow  fever,  at 
various  intervals  prior  to  the  biting. 

In  prosecuting  the  first  part  of  our  work,  we  isolated  a  variety  of 
bacteria,  but  of  these  we  do  not  propose  to  speak  at  present.     It  will 
suffice  for  our  purpose  if  we  state  the  results  as  regards  the  findii 
bacillus  icteroides,  leaving  the  mention  of  other  bacteria  to  our  detailed 
report. 

The  cases  studied  during  the  Quemados  epidemic  had  been  diag- 
nosed by  a  board  of  physicians  selected  largely  by  reason  of  their 
familiarity  with  yellow  fever.     This  board  consisted  of  Drs.  Nicola 
Silverio,  Manuel  Herera,  Eduardo  Angles,  and  Acting  Asst.  Si 
Roger  P.  Ames  and  Jesse  W.  Lazear,  United  States  Army. 

Those  studied  in  Ilabana  were  patients  in  Las  Animas  Hospital 
and  had  been  diagnosed  as  such  by  a  board  of  distinguished  practi- 
tioners of  that  city. 

An  examination  of  Table  I  will  show  the  character  of  the  attacks. 

The  milder  cases  studied,  few  in  number -,  were  attended  by  jaundice 
and  albumen  in  the  urine. 

>  Reprinted  from  the  Proceeding*  of  the  Twenty-eighth  Annual  Meeting  of  the  American  Public  Health 
Aaocfatlon,  Indianapolis,  Ind.,  CM.  22, 23. 24, 25,  and  2ft,  1900. 
«  Died  of  yellow  fever  at  Columbia  Barracks,  Cuba,  Sept.  25, 1900. 


YELLOW   FEVEK. 


57 


I.  BACILLUS  ICTEROIDES   (SANARELLI)  AS  THE  CAUSE  OF  YELLOW 

FEVER. 

The  claim  of  Sanarelli  for  the  specific  character  of  B.  icteroides  as 
the  causative  agent  in  yellow  fever  has  excited  such  wide  attention 
since  the  publication  of  his  observations  that  it  seemed  to  us  of  the 
first  importance  to  give  our  undivided  attention  to  the  isolation  of 
this  microorganism  from  the  blood  of  those  sick  with  yellow  fever 
and  from  the  blood  and  organs  of  yellow-fever  cadavers. 

(A)    CULTURES    TAKEN    FROM    THE    BLOOD   DURING    LIFE. 

The  method  followed  was  that  ordinarily  used  in  an  attempt  to 
isolate  bacteria  from  the  circulating  blood,  viz,  from  a  vein  at  the 
bend  of  the  elbow  a  sufficient  quantity  of  blood  was  taken  with  a 
hypodermic  syringe,  made  sterile  by  boiling,  and  after  careful  cleans- 
ing of  the  skin  with  soap  and  water,  followed  by  equal  parts  of  abso- 
lute alcohol  and  ether,  and  1-2000  bichloride  solution. 

Exceptionally,  the  blood  withdrawn  was  plated  on  agar,  but  as  a 
rule  it  was  immediately  transferred  to  sterile  bouillon  tubes  (10  c.  c.) 
in  quantities  of  0.5  c.  c.  to  each  of  several  tubes.  These  were  then 
incubated  at  35°  to  37°  C.  for  a  period  of  one  week.  They  were 
examined  daily,  and  if  growth  was  observed  plates  in  agar  or  gelatine, 
or  both,  were  made  and  the  colonies  carefully  studied  by  transference 
to  ordinary  laboratory  media. 

Eighteen  cases  have  thus  been  carefully  studied;  of  these  11 
were  designated  as  " severe"  cases  of  yellow  fever,  with  4  deaths;  3  as 
" well-marked"  cases,  with  no  deaths;  and  4  as  "mild"  cases,  with 
no  deaths. 

From  these  18  cases  blood  cultures  were  made,  as  shown  in  the 
following  table: 

TABLE  I. — Blood  cultures  during  life. 


Day  of  disease. 

Character  of  attack. 

Number 
of  cul- 
tures. 

Number 
of  bouil- 
lon tubes 
inocu- 
lated. 

B.  icteroides. 

First 

Severe                                                             

3- 

14, 

Negative. 

Do 

Well  marked 

1 

4 

Do. 

Do 

Mild                                                      

1 

3 

Do. 

Second 

Severe                                                                  

6 

18 

Do. 

Do 

Well  marked                                        

1 

2 

Do. 

Do 

Mild                                                                   

1 

«3 

Do. 

Third 

Severe                                          

7 

a  18 

Do. 

Do 

Mild                                                            

2 

4 

Do. 

Fourth 

5 

14 

Do. 

Do 

Well  marked               '                       

2 

6 

Do. 

Do 

Mild                                                                

1 

1 

Do. 

Fifth 

Severe                                            

5 

U2 

Do. 

Do 

Well  marked                                            

1 

3 

Do. 

Do 

Mild                                           

1 

1 

Do. 

Sixth 

4 

6 

Do. 

Do 

Well  marked                       

I 

2 

Do. 

Seventh 

1 

2 

Do. 

Do 

Well  marked                                               

1 

2 

Do. 

Eighth 

Severe                                      

2 

6 

Do. 

Do 

Well  marked                                           

1 

2 

Do. 

Ninth 

Severe                              

1 

2 

.Do. 

f- 

1  3  agar  plates. 


2  6  agar  pla! 


Number  of  cultures 

Number  of  bouillon  tubes  inoculated. 
Number  of  agar  plates 


48 
115 
15 


r.s 


YKLLOXV     FKVKR. 


It  will  be  seen  that  of  48  separate  cultures  made  from  the  blood  on 
various  days  of  the  disease  and  representing  115  bouillon  inoculat  i.  >ns 
and  18  agar  plates,  we  failed  to  find  BadMua  icteroides  in  any  of  our 
tubes  or  plates. 

The  results  of  cultures  taken  hi  18  l  cases  of  unmistakable  yell<>\\ 
fever.  mi  \  arious  days  of  the  disease  and  in  some  cases  on  ev«  TV  day 
from  the  onset  to  death  or  recovery,  would  seem  to  exclude  the 
presence  of  Bacillus  icteraides  in  the  l»l<»«.d  of  these  cases  durini:  life. 

1  1  will  therefore  be  seen  that  while  Wasdin  and  Gedd  ings  inking 
cultures  from  the  ear  lobe  (Report  on  the  Cause  of  Yellow  Krver. 
1899),  record  that  "in  the  blood  of  yellow-fever  cases  extract  eel 
during  life  BaciUus  icteroides  has  been  found  in  13  of  the  14  cases, 
with  1  negative"  (92.85  per  cent),  we,  by  withdrawing  blond  from 
the  veins  of  18  patients,  have  to  record  100  per  cent  of  failures. 

We  have  already  stated  that  \\e  will  reserve  for  a  lat.-r  report  a 
description  of  the  hacteria  isolated  from  tlie  blond  in  these  cases.  We 
now  remark  that  but  tew  organisms  wore  obtained  and  that,  as  a 
rule,  our  hlood  cultures  guvi'  no  growth  whatever. 


(B)    CULTURES   FROM    YELLOW-FEVER   CADAVERS. 

We  tried  to  obtain  autopsies  very  soon  after  death  and  sometimes 
•  •ed  in  doing  so.  Tubes  containing  about  10  c.  c.  of  llesh-peptone 
bouillon  were  generally  used  for  the  first  inoculation,  direct  from  the 
blood  and  organs.  As  soon  as  the  laboratory  was  reached,  aga  r  plates 
were  made  from  these  inoculated  bouillon  tubes,  the  former  as  well 
as  the  latter  being  then  incubated  at  35°-37°  C.  In  nearh  every 
case  gelatin  plates  were  also  made  from  the  recently  inocul 
bouillon  tubes  and  kept  at  a  temperature  of  19°-20°  C. 

If  colonies  were  found  in  the  agar  or  gelatin  plates  on  the  following 
days,  the  corresponding  bouillon  tubes  were  also  plated  on  agar 
gelatin.  The  bacteria  thus  found  in  our  plates  were  carefully  iso- 
lated and  studied  upon  the  usual  nutritive  media,  so  as  to  enaole  us 
to  identify  them  it  possible.  We  will  here  content  ourselves  \\ith 
giving  the  results  as  regards  the  presence  of  B.  icteroides  only. 

TABLE  II. 


No.  of 

BMI 

Day  of  disease. 

Time  of  autopsy. 

Source  of  culture. 

B.  icteroides. 

1 

Seventh     . 

2  hours  after  death    .  . 

Blood,  liver,  spleen,  kidney.  .  . 

Negative. 

2 

Sixth 

13  hours  after  death 

do 

Do 

3 

Fourth 

8  hours  after  death 

do 

Do 

. 
Fourth 

4  hours  after  death.... 
.  .  .do  

Abdominal  cavity,  blood,  liver,  spleen, 
kidney,  bile,  duodenum. 
Blood,  liver,  spleen,  kidney,  bile,  duode- 

Do. 
Do. 

Sixth  

6}  hours  after  death  .  .  . 

num. 
Abdominal  cavity,   blood,   pericardia! 

Do. 

do. 
do. 

50  minutes  after  death. 
^  hour  after  death  

lluid.  IUIIK.  Spleen,  kidney,  lj\. 
duodenum 
Blood,  lung,  liver,  spleen,  kidn- 
jejunum. 
Blood,  lung,  liver,  spleen,  kidney,  urine, 

Do. 

Fourth 

2  hours  after  death 

Mllllll  i'ltr    li'ir 

Liver,  spleen,  small  intestine 

Do. 

10 

mfe 

7  h<,  i:     iffest  •!<•  ith 

.  idney,  spleen,  small  intestine.  .  , 

Do. 

11 

Third 

}  hour  after  death 

.  idneyi  spleen' 

Do. 

'  Cultures  from  the  blood  during  life  had  been  taken  by  Dr.  Lazeur  in  three  other  cases  of  yellow  fever, 

•     .'     -        ••-.-.;.•    .,.'.,.:  ,....•,;,,        .;.;/..:.,",:  .  •,          ,•.,    ...    .    .  ,  ,,:.    v.  M,  '     ,  ultunvs 

had  been  taken  can  not  be  ascertained.    These  cultures  were  negative  as  regards  the  finding  of  SanarelU's 


YELLOW   FEVER.  59 

Our  failure  to  isolate  B.  icteroides  in  these  11  autopsies  of  yellow- 
fever  patients  was  a  result  which  we  had  not  anticipated.  One  of  us 
(Agramonte)  who  at  Santiago,  Cuba,  during  the  epidemic  of  1898, 
succeeded  in  finding  B.  icteroides  in  33  per  cent  of  his  autopsies,  has 
been  much  surprised  at  the  absence  of  this  bacillus  in  cultures  from 
cadavers  sectioned  in  Habana  during  the  present  year.  In  2  of  the 
11  cases  we  had  reason  to  believe  that  from  the  character  of  colonies 
seen  in  gelatin  plates  we  would  be  able  to  isolate  B.  icteroides.  These 
colonies,  however,  when  transferred  to  other  media  and  carefully 
studied,  did  not  prove  to  be  this  bacillus.  We  wonder  whether  other 
observers  have  occasionally  relied  upon  the  appearance  of  colonies  in 
gelatin  plates  without  further  study.  We  only  mention  this  as  a  pos- 
sible explanation  of  the  large  percentage  of  positive  results  recorded 
by  some  observers. 

Pothier,  of  New  Orleans,  La.,  only  succeeded,  however,  in  isolating 
B.  icteroides  in  3  out  of  51  autopsies.  (Journal  of  American  Medical 
Association,  Apr.  16,  1898.) 

Lutz  (Revista  D'Igiene  e  Sanita  Publica,  XI,  No.  13,  July,  1900, 
pp.  474-475),  says,  as  the  result  of  his  extensive  observations  on  yellow 
fever,  that  Bacillus  icteroides  can  not  be  found  by  present  laboratory 
methods  in  more  than  half  of  the  cases  of  yellow  fever,  and  that  when 
present  the  colonies  are  few  in  number. 

It  is  possible  that  our  future  autopsies  may  give  more  favorable 
results  as  regards  B.  icteroides. 

II.  THE  MOSQUITO  AS  THE  HOST  OF  THE  PARASITE  OF  YELLOW  FEVER. 

Having  failed  to  isolate  B.  icteroides  either  from  the  blood  during 
life  or  from  the  blood  and  organs  of  cadavers,  two  courses  of  procedure 
in  our  further  investigations  appeared  to  be  deserving  of  attention,  viz, 
first,  a  careful  study  of  the  intestinal  flora  in  yellow  fever  in  compari- 
son with  the  bacteria  that  we  might  isolate  from  the  intestinal  canal  of 
healthy  individuals  in  this  vicinity  or  of  those  sick  with  other  dis- 
eases; or,  secondly,  to  give  our  attention  to  the  theory  of  the  propaga- 
tion of  yellow  fever  by  means  of  the  mosquito — a  theory  first  advanced 
and  ingeniously  discussed  by  Dr.  Carlos  J.  Finlay,  of  Habana,  in  1881. 
(Anales  de  la  Real  Academia,  voTTS,  ISSlTpf  liT^lBQ.)  ^ 

We  were  influenced  to  take  up  the  second  line  of  investigation  by 
reason  of  the  well-known  facts  connected  with  the  epidemiology  of 
this  disease,  and  of  course  by  the  brilliant  work  of  Ross  and  the  Italian 
observers  in  connection  with  the  theory  of  the  propagation  of  malaria 
by  the  mosquito. 

We  were  also  much  impressed  by  the  valuable  observations  made 
at  Orwood  and  Taylor,  Miss.,  during  the  year  1898,  by  Surg.  Henry 
R.  Carter,  United  States  Marine-Hospital  Service.  A  note  on  the 
interval  between  infecting  and  secondary  cases  of  yellow  fever,  etc. 
(Reprint  from  New  Orleans  Medical  Journal,  May,  1900.)  We  do  not 
believe  that  sufficient  importance  has  been  accorded  these  painstaking 
and  valuable  data.  We  observe  that  the  members  of  the  yellow-fever 
commission  of  the  Liverpool  School  of  Tropical  Medicine,  DBS.  Dur- 
ham and  Myers,  to  whom  we  had  the  pleasure  of  submitting  Carter's 
observations,  have  been  equally  impressed  by  their  importance. 
(British  Medical  Journal,  Sept.  8,  1900,  pp.  656-657.) 


60 

The  circumstances  under  which  Carter  worked  were  favorable  for 
recording  with  considerable  accurac\  the  interval  between  the  time  of 
arrival  of  infecting  cases  in  isolated  farmhouses  and  the  occurrence  of 
secondary  cases  in  these  houses.  Accord  in  ter,  'the  period 

from  the  first  < infect ing)  case  to  the  first  group  of  cases  infected  at 
these  houses  is  generally  from  two  to  three  \ 

The  houses  having  now  become  infected,  susceptible  individuals 
there  siting  the  houses  for  a  few  hours  fall  side  with  the  disease 

in  the  usual  period  of  incubation     one  n  days. 

her  observations  made  by  u>  >ince  our  arrival  conlirmed  (  arter's 
hisions.  thus  pointing,  as  it  seemed  to  us,  to  the  pr.  !  an 

intermediate  host,  such  as  the  mosquito,  which,  having  taken  tin- 
parasite  into  its  stomach  soon  after  the  entrance  of  the  patient  into 
the  noninfected  house,  was  able  after  a  certain  interval  to  reconvey 
the  infecting  agent  to  other  individuals,  thereby  converting  a  nmi- 
infectcd  house  into  an  "infected  ''  house.  This  interval  would  apnear 
to  be  from  9  to  16  days  (allowing  for  the  period  of  incubation  '.  which 
agrees  fairly  closely  with  the  time  required  for  the  passage  of  the 
malarial  parasite  from  the  stomach  of  the  mosquito  to  its  salivary 
glands. 

In  view  of  the  foregoing  observations  we  concluded  to  test  the 
theory  of  Finlay  on  human  beings.  According  to  this  author's  oi 
vation  of  numerous  inoculations  in  90  individuals,  the  application  of 
one  or  two  contaminated  mosquitoes  is  not  dangerous,  out  followed 
in  about  18  per  cent  by  an  attack  of  what  he  considers  to  be  very 
benign  yellow  fever  at  the  most. 

We  Here  desire  to  express  our  sincere  thanks  to  Dr.  Finlay,  who 
accorded  us  a  most  courteous  interview,  and  has  gladly  placecl  at  our 
disposal  his  several  publications  relating  to  yellow  fever  during  tin- 
past  19  years;  and  also  for  ova  of  the  species  of  mosquito  with 
which  he  had  made  his  several  inoculations.  An  important 
tion  to  be  here  recorded  is  that,  according  to  Finlay  s  statement.  :;n 
days  prior  to  our  visit,  these  ova  had  been  deposited  by  a  female  just 
at'theedgeof  the  water  in  a  small  basin,  whose  contents  had 
allowed  to  slightly  evaporate,  so  that  these  ova  were  at  the  time  of  our 
visit  entirely  above  contact  with  the  water.  Notwithstanding  this 
long  interval  after  deposition,  they  were  prompt Iv  converted  into  the 
larval  stage,  after  a  snort  period,  by  raising  the  level  of  the  water  in 
the  basin. 

With  the  mosquitoes  thus  obtained  we  have  been  able  to  conduct 
our  experiments.  Specimens  of  this  mosquito  forwarded  to  Mr.  L. 
O.  Howard,  entomologist,  Department  of  Agriculture,  Washington, 
D.  C.,  were  kindly  identified  as  CulexfasciatusF&br. 

In  this  preliminary  note  we  have  not  space  to  refer  at  length  to 
the  various  interesting  and  valuable  contributions  made  by  Kinlay  to 
the  mosquito  theory  for  the  propagation  of  yellow  fever.  In  addition 
to  the  paper  already  quotea,  his  most  valuable  contributions  to  this 
important  theorv  are  to  be  found  in  the  articles  designated  as  follows: 
Estadistica  de  las  Inoculaciones  con  mosquitos  contaminados,  ct< •., 
reprint, Havana,  1891  :  Fiebre  Amarilla. Estudio Clinico  Patnl.,gimy 
Ktiologico,  reprint.  Habana,  1895;  and  Yellow  l«Y\er  Immunity- 
Modes  of  Propagation:  Mosquito  Theory,  8th  Congress  of  Interna- 
tional Hygienic  and  Demography,  Budapest,  1894. 


YELLOW   FEVER.  61 

His  present  views  on  this  subject  may  be  stated  in  his  own  language : 
"  First,  reproduction  of  the  disease,  in  a  mild  form,  within  5  to 
25  days  after  having  applied  contaminated  mosquitoes  to  susceptible 
subjects.  Second,  partial  or  complete  immunity  against  yellow  fever 
obtained  when  even  no  pathogenous  manifestation  had  followed 
those  inoculations."  (Medical  Eecord,  vol  55,  No.  21,  May  27,  1899.) 

Without  reviewing  the  cases  regarded  as  mild  forms  by  the  author 
of  this  theory,  we  believe  that  he  has  not  as  yet  succeeded  in  repro- 
ducing a  well-marked  attack  of  yellow  fever  within  the  usual  period 
of  incubation  of  the  disease,  attended  by  albumen  and  jaundice,  and 
in  which  all  other  sources  of  infection  could  be  excluded. 

The  experiments  made  by  us  on  eleven  nonimmune  individuals  are 
embraced  in  the  following  table,  which  should  be  carefully  studied. 

The  mosquito  used  in  all  cases  was  Culexfasciatus  Fabr. 


62 


YELLOW   FEVER, 
o  - 


t 


li* 


^-  —  —  —  —  —  —    Ct          — 


f.'.  lion  of 
qulto  and 
culation. 


SOOtf  0«C«OW« 

111    1! 


"OR  :  "o 


S  :  :  : 


:c' 


lilll 

-v:fafa< 


I 


YELLOW   FEVER.  63 

It  will  be  seen  that  we  record  9  negative  and  2  positive  results. 
It  is,  we  think,  important  to  observe  that  of  the  9  failures  to  infect, 
the  tune  elapsing  between  the  biting  of  the  mosquito  and  the  inocu- 
lation of  the  healthy  subject  varied  in  7  cases  from  2  to  8  days  (Nos.  1, 
2,  3,  4,  5,  7,  and  9),  and  in  the  remaining  two  from  10  to  13  days  (Nos. 
6  and  8). 

Five  individuals  out  of  the  9  who  failed  to  show  any  result  (Nos. 
2,  3,  4,  5,  and  6)  were  inoculated  by  mosquitoes  that  had  bitten  very 
mild  cases  of  yellow  fever  on  the  fifth  day  of  the  disease,  and  one 
individual  by  a  mosquito  that  had  bitten  a  mild  case  of  yellow  fever 
on  the  seventh  day  of  the  disease.  (This  latter  patient  was  discharged 
from  hospital  3  days  later.)  To  this  fact  may  possibly  be  attributed 
the  negative  results.  Of  the  remaining  3  negative  cases  (Nos.  7,  8, 
and  9),  and  which  had  been  inoculated  by  mosquitoes  that  had  bitten 
severe  cases  of  the  disease,  the  interval  between  the  bite  and  the 
inoculation  varied  from  2  to  6  days. 

In  the  2  cases  (Nos.  6  and  8)  where  the  interval  was  respectively 
10  and  13  days,  the  inoculations  had  been  made  with  mosquitoes  that 
had  bitten  very  mild  cases  of  yellow  fever  on  the  fifth  day  of  the 
attack.  No.  8  was  also  bitten  by  a  mosquito  which  had  been  infected 
by  a  severe  case  of  yellow  fever  3  days  before. 

We  refrain  from  commenting  further  at  this  time  upon  the  9 
negative  cases,  preferring  to  record  the  results  obtained  rather  than 
to  indulge  in  speculation. 

Of  the  two  cases  which  we  have  recorded  as  positive  in  Table  III, 
we  now  propose  to  speak  at  greater  length.  i 

Case  10, — Dr.  James  Carroll,  acting  assistant  surgeon,  United  States  Army,  a  member  1 
of  this  board,  was  bitten  at  2  p.  m.,  August  27,  1900,  by  Culexfasciatus.  This  particu-  ) 
lar  mosquito  had  bitten  a  severe  case  of  yellow  fever  on  the  second  day  of  the  disease  12  \ 
days  before;  a  mild  case  of  yellow  fever,  on  the  first  day  of  the  attack,  6  days  preceding;,/ 
a  severe  case  of  yellow  fever,  on  the  second  day  of  the  attack,  4  days  before;  a  mild  I 
case  of  yellow  fever,  on  the  second  day  of  attack,  2  days  before  inoculation. 

Dr.  Carroll  remained  well  until  the  afternoon  of  the  29th,  when  he  states  that  he 
felt  tired,  and  for  this  reason,  when  on  a  visit  to  Las  Animas  Hospital,  the  same  after- 
noon (29th),  some  time  between  4  and  6  p.  m.,  after  visiting  a  few  patients,  he  left 
the  wards  and  waited  outside  on  the  porch,  while  his  companions  remained  in  the 
wards. 

August  30:  During  the  afternoon,  although  not  feeling  well,  Dr.  Carroll  visited  La 
Playa,  distant  about  1J  miles  from  Columbia  Barracks,  and  took  a  sea  bath. 

August  31 ,  a.  m.:  Dr.  Carroll  realized  that  he  was  sick  and  that  he  had  fever,  although 
he  refrained  from  taking  his  temperature,  but  did  visit  the  laboratory,  distant  about 
140  yards,  for  the  purpose  of  examining  his  blood  for  the  malarial  parasite.  The 
examination  was  negative.  During  the  afternoon  he  was  compelled  to  take  to  his 
bed.  At  7  p.  m.  temperature  was  102°  F.  No  headache  nor  backache;  only  a  sense 
of  great  lassitude.  Eyes  injected  and  face  suffused. 

September  1,  7  a.  m.:  Temperature  102°  F.  Blood  again  carefully  examined  by  Dr. 
Lazear  with  negative  results. 

11  a.m.:  Temperature  102°. 

The  case  having  been  diagnosed  as  one  of  yellow  fever,  Dr.  Carroll  was  at  noon , 
removed  to  the  yellow  fever  wards. 

9  p.  m.:  Temperature  102.8°,  pulse  90;  12  o'clock  midnight,  temperature  103.4°, 
pulse  84. 

September  2,  3  a.  m.:  Temperature  103.6°,  pulse  80.  A  trace  of  albumen  was  now 
found  in  the  urine.  The  subsequent  history  of  the  case  was  one  of  severe  yellow 
fever.  Jaundice  appeared  on  September  3. 

The  accompanying  chart  No.  1  contains  all  of  the  necessary  data. 

The  question  of  diagnosis  having  been  clearly  and  easily  estab- 
lished, it  now  becomes  important  to  follow  Dr.  Carroll's  movements 
for  a  period  of  10  days  preceding  the  mosquito  inoculation,  and 


64 


YKLLONV    FKYEK. 


YELLOW    FEVER.  65 

during  the  period  elapsing  from  the  bite  of  the  insect  until  the  com- 
mencement of  the  attack. 

On  August  21,  22,  and  23,  Dr.  Carroll  was  at  Columbia  Barracks, 
outside  of  the  epidemic  zone.  On  August  24  he  visited  the  autopsy 
room  of  Military  Hospital  No.  1,  which  is  situated  on  Principe  Hill 
overlooking  the  city  of  Habana.  He  was  present  in  this  autopsy 
room  while  an  autopsy  was  made  by  Dr.  Agramonte  on  a  case  of  per- 
nicious malarial  fever.  Dr.  Carroll  only  took  cultures  from  the 
blood  and  organs  as  the  section  proceeded.  He  was  there  about  half 
an  hour  and  then  returned  to  Columbia  Barracks.  Subsequent 
microscopic  study  of  sections  of  the  liver  and  spleen  showed  that  the 
case  autopsied  on  the  29th  was  really  a  case  of  pernicious  malarial 
fever. 

It  should  be  stated  that  although  cases  of  yellow  fever  are  not 
admitted  to  Military  Hospital  No.  1,  an  English  sea  captain  had  been 
admitted  to  its  wards  a  few  days  before,  whose  case  developed  into 
one  of  yellow  fever  with  fatal  result,  and  the  body  had  been  autopsied 
by  Dr.  Agramonte  in  this  dead  room  on  the  day  preceding  Dr.  Car- 
roll's visit  to  it.  ^ 

According  to  Dr.  Carroll,  the  room  was  by  no  means  in  a  cleanly 
condition.     As  Dr.  Carroll's  visit  to  this  room  was  made  on  August  24,  * 
and  as  he  began  to  complain  on  August  29,  about  the  average  period 
of  incubation  of  yellow  fever,  there  is  a  possible  chance  for  infection 
in  this  way.     We  must  call  attention,  however,  to  the  fact  that  Dr. '' 
Agramonte,  whenever  he  performs  an  autopsy  in  this  room,  is  always 
attended  by  a  young  soldier  of  the  Hospital  Corps,  United  States 
Army,  who  is  detailed  for  that  purpose,  and  whose  duty  it  is  to  assist - 
and  to  afterwards  attend  to  the  cleaning  of  the  autopsy  table.     This 
soldier,  a  nonimmune  American,  was  present  when  Dr.  Carroll  was: 
there  and  remained  afterwards  to  attend  to  his  duties.     He  has  notj 
contracted  yellow-fever  by  his  duties  in  this  room  from  time  to  time/ 
Our  own  experience  would  seem  to  accord  with  that  of  others,  viz, 
that  attendance  upon   autopsies   and  the  handling  of  portions  of  | 
organs  of  yellow-fever  cases  removed  to  the  laboratory  is  unattended" 
with  danger.     Certainly  the  three  nonimmune  members  of  this  board, ; 
up  to  the  time  of  these  mosquito  inoculations,  had  during  the  pastj 
three  months  come  in  close  contact  with  the  dead  bodies  and  organs 
of  yellow-fever  cases,  freely  handling  and  examining  these  organs, 
including  the  small  intestine,  even  kept  at  thermostat  temperature 
for  24  hours,  without  contracting  the  disease.     We  have,  of  course, 
never  neglected  to  cleanse  our  hands  with  disinfectants. 

Dr.  Carroll  upon  his  visit  to  the  before-mentioned  dead  room  only 
used  the  platinum  loop  for  taking  cultures  and  did  not  come  in  contact 
with  the  autopsy  table. 

The  only  other  opportunity  for  infection  in  his  case  would  appear 
to  have  been  during  his  visit  to  Las  Animas  Hospital,  situated  in  the 
suburbs  of  Habana,  as  here  yellow-fever  patients  are  admitted  in 
large  numbers.  We  have  already  pointed  out  that  Dr.  Carroll  was 
complaining  of  lassitude  at  the  hour  of  his  visit,  which  was  about  50 
hours  after  his  inoculation  with  the  contaminated  mosquito.  We 
have  also  called  attention  to  the  fact  that  he  remained  for  the  greater 
part  of  his  visit  outside  of  the  hospital,  on  the  piazza.  This  would 

79965°— S.  Doc.  822,  61-3 5 


66  YKU.oU      i   l.VER. 

appear  to  caM   doubt  upon  hi>  \  Uit   to  Las  Aninias  as  the  sour- 
his  infection. 

Wo  do  not  wish  to  be  understood  as  unnecessarily  seeking  to  lay 
too  much  emphasis  upon  the  exclusion  in  this  ease  of  other  sources 
of  infection  than  the  mosquito,  as  we  fully  appreciate  that  Dr.  Carroll 
had  been  on  two  occasions  within  the  epidemic  zone  during  the  week 

•  •ding  his  attack  of  yellow  fever.     His  movements  on  these  ,. 
sions  we  have  already  given. 

We  will  again  refer  to  Dr.  Carroll's  case  after  we  have  given  the 
history  of  case  No.  11,  which  we  have  designated  as  our  second  posi- 
tive result.  ^  *v+&  /*  &<-**-  'fci+vjt  fB  Jjtt  C^^r 

COM  11. — X.  Y.,  white,  American,  a  resident  of  me  military  reservation  of  <  \.hnn- 
bia  Barracks,  was  bin  (Mi  during  the  forenoon  of  the  31st  day  of  A  ">n,  1>\-  ihe 

same  mosquito  that  had  bitten  case  10  (I  M  »  an.. 11)  4  days  before,  and  which  in  tin- 
meanwhile  had  bitten  a  mild  case  of  yellow  fever  (first  day)  2  dayn  before  being  applied 
toX  Y. 

\.  V .  was  also  bitten  by  a  second  mosquito  that  had  been  applied  to  a 
of  yellow  fever  (second  day)  U  days  before,  and  to  2  mild  cases  (HM-..M«|  day)  1  and  10 
days  previously;  also,  by  a  third  mosquito  that  had  bitten  a  fatal  case  "i"  yrll<>\\ 
(second  day)  12  days  before,  a  severe  case  (first  day)  2  days  bef> 
(first,  second,  and  third  day)  4,  6,  and  10  days  before;  finally,  by  a  fourth  mosquito 
that  had  bitten  3  severe  cases  of  yellow  fever  (all  on  the  first  day)  L'  days 

previously,  and  1  mild  case  (second  dav)  6  days  before.     (Vide  Ta i •!<•  111.) 

It  will  thus  be  seen  that  X.  Y.  was  oitten  by  4  mosquitoes,  2  of  whi^h  had  i 
severe  (fatal)  cases  of  yellow  fever  12  days  previously,  one  of  which  had  hit  t 
case  (second  day)  16  days  before,  and  one  which  had  bitten  a  severe  case  (lir-t  day; 

8  days  before. 

September  25. — X.  Y.  began  to  experience  a  sense  of  dizziness  and  di.-im  linai 
work.    This  was  just  5  days  from  the  time  of  the  mosquito  inoculation. 

Twenty-four  hours  later,  still  dizzy  and  light-headed  in  attempting  to  move  about. 
During  the  afternoon  (sixth  day  after  inoculation)  chilly  sensations,  followed  \>\ 
and  restlessness  during  the  night. 

On  the  following  day  (seventh  day  after  inoculation),  8  a.  m.,  temperature  1  ():_'.  ^  I  . 
eyes  slightly  injected,  lace  suffused.  Patient  removed  to  the  yellow  fever  . 

9  a.  m.,  temperature  103°  F.,  pulse  GG.     A  trace  of  albumen  was  found  in  the  urine 
during  the  afternoon  (third  day  of  the  attack).     This  increased  during  the  following 
days.     Conjunctive  slightly  jaundiced  on  the  fourth  day  of  disease,  which  was  more 
distinct  and  could  be  plainly  seen  on  anterior  aspect  of  chest  on  the  fifth  and  following 
day.     Bleeding  from  the  gums  was  noticed  on  the  third  and  subsequent 
admission.     Repeated  examinations  of  the  blood  failed  to  show  any  malarial  parasites. 

The  course  of  the  fever,  the  appearance  of  albumen  in  the  urine, 
with  jaundice  and  hemorrhage  from  the  gums,  together  with  the  slow 
pulse,  all  pointed  distinctly  to  the  diagnosis  of  yellow  fever.  His 
attending  physician,  Dr.  lloger  P.  Ames,  United  States  Army,  an 
expert  in  the  diagnosis  and  treatment  of  this  disease,  did  n<>i  lie-it  ate 
to  diagnose  X.  Y.'s  attack  as  one  of  "well-pronounced  yello\v  fe\ 
Dr.  Ames  was  not  cognizant  of  the  method  of  inoctilat  ion  in  this  case. 
(Vide,  Chart  EL) 

The  diagnosis,  therefore,  not  being  in  doubt,  we  must  follow  this 
patient's  movements  during  the  10  days  preceding  the  bite  of  the 
mosquitoes  and  from  this  time  until  5  days  later,  when  the  attack 
began.  It  so  happens  that  we  can  follow  X.  Y.'s  movements  I'm-  a 
much  longer  period.  Fifty-seven  days  prior  to  his  inoculation,  he 
spent  a  day  and  night  in  the  city  of  Habana.  Sixteen  days  before  the 
inoculation,  he  rode  on  horseback  with  6  other  nonimmunes  a  dis- 
tance of  about  IJ  mile^  toward  the  seashore  and  returned  to  his 
dwelling,  without  in  the  meantime  dismounting  from  his  limse. 

From  this  time  until  hi^  complete  convalescence  was  established,  lie 


YELLOW    FEVER. 


67 


had  remained  within  the  immediate  vicinity  of  his  home.  So  that  it 
may  be  positively  stated  that  X.  Y.  had  not  absented  himself  from  the 
military  reservation  of  Columbia  Barracks  during  a  period  of  57 
days  prior  to  his  inoculation  (with  the  exception  above  stated), 
nor  between  the  date  of  his  inoculation  and  the  establishment  of  con- 
valescence. 

Let  us  now  inquire  whether  the  military  reservation  of  Columbia 
Barracks  is  outside  of  the  epidemic  zone  of  yellow  fever.     To  this 


N 


44 


^?o 


^S 


§  $  s 

!t^ 


K*5:5 

fc^ 
kll 


V 

&t 

»s 


1>     ^    v* 

?W 


\ 


we  answer  that  since  the  commencement  of  the  present  epidemic  of 
yellow  fever  in  Habana,  dating  from  May,  1900,  the  average  monthly 
population  of  this  station,  including  civilian  employees,  has  been 
1,400,  nearly  all  of  whom  are  young  nonimmunes.  * 

There  have  occurred  amongst  this  nonimmune  population  from 
May  1  to  October  13,  1900,  16  cases  of  yellow  fever,  all  of  which 
have  been  easily  and  readily  traced  to  a  visit  to  within  the  boundaries 
of  the  epidemic  zone,  except  cases  10  and  11  of  Table  III,  and  1 


68 

other  case  of  which  wo  shall  presently  speak.     T 
ributed  as  follows: 

rases. 

May  24... 
June  10... 
Jum« 

June  19... 
June  21... 
June  29... 
July  9.. 
July  26. 
July  29. 


u 

Aui.16. 

Au.vSl 

Sept.  19  . 

Total 

Ten  of  these  cases  have  occurred   amount    an    average   mnn: 
military  population  of  1,295  men,  and  6  cases  in  an  average  Civilian 
population  of  105. 

Whenever  these  cases  have  occurred,  as  soon  as  the  patient 
been  removed  to  hospital  most  careful  mea*i 
been  immediately  carried  out  by  a  trained  sanitary  squad,  tmd: 
personal  supervision  of  a  medical  ollicer.  I  of 

destruction  by  fire  of  mattresses,  the  disinfection 
clothing  with  1  to  500  bichloride  solution,  and  the  application  o 
same  solution  freely  to  the  ceiling,  walls,  and  floor- 
force  pump. 

We  repeat  that  no  case  has  ever  been  connected  with  a  preceding 
case,  but  that  the  source  of  infection  has  he-. 
occurred  during  the  individual's  visit  to  Habana,  r>  mil.- 
to  some  other  nearer  Cuban  settlement. 

We  now  invite  attention  to  the  fact  that  from  August  17  to  ( )< -tnh< -r 
13,  a  period  of  57  days,  only  3  cases  of  yellow  fevrr  have  occu 
amongst  this  population  of  1,400  nonimnmm  and    \\  e 

consider  it  very  important  to  note  that  two  of  these  had 
within  5  days  of  the  commencement  of  their  attack,  by  <  n/itamii 
mosquitoes. 

Taken  in  connection  with  case  'J.  in  which 
find  any  other  source  of  infection  than  the  bite  of 
quito,  5  days  preceding  the  at  t  ark.  the 
lO-Table  III)  Decomes  strongly  confirmatory  of  the  sa  n. 

We  will  now  briefly  give  the  history  of  the  t  hird  case  of  yell- 
that  has  occurred  at  Columbia  Barracks  during  the  period  A 
to  October  13,  1900. 

In  the  light  of  cases  10  and  11  we  consider  this  case  of  suflicicnt 
importance  to  be  here  Included, especially  as  it  is  one  that  might  he 
possibly  designated  as  a  case  of  accidental  ini'eetion  by  a  mo 

Cote. — Dr.  Jesse  \V .  Lazear.  acting  assistant  surgeon.  United  States  .A  i 
of  this  board,  was  bin,  n  Hi,  1900  (case  » 

fatciatus)  which  10  davs  previously  had  be<Mi  <-MIII;IH  mild 

case  of  yellow  fever  (fifth  day).    No  appreciable  di.-tiirbanro  of  health  i< -II »\\< •<!  ihiw 
inociikii; 

1900  (forenoon):  Dr.  l^azear,  v  hil- 
and  while  collecting  blood  from  yellow-fever  pat  i< 


V  111, LOW    FEVKK.  69 

mosquito  (species  undertermined).  As  Dr.  Lazear  had  been  previously  bitten  by  a 
contaminated  insect  without  after  effects,  he  deliberately  allowed  this  particular 
mosquito,  which  had  settled  on  the  back  of  his  hand,  to  remain  until  it  had  satisfied 
its  hunger. 

On  the  evening  of  September  18,  5  days  after  the  bite,  Dr.  Lazear  complained  of 
feeling  "out  of  sorts,"  and  had  a  chill  at  8  p.  m. 

September  19:  Twelve  o'clock  noon,  temperature  102.4°,  pulse,  112.  Eyes  injected, 
face  suffused;  3  p.  m.,  temperature,  103.4°,  pulse,  104;  6  p.  m.,  temperature,  103.8°, 
pulse,  106.  Albumen  appeared  in  the  urine.  Jaundice  appeared  on  the  third  day. 
The  subsequent  history  of  this  case  was  one  of  progressive  and  fatal  yellow  fever,  the 
death  of  our  much  lamented  colleague  having  occurred  on  the  evening  of  Septem- 
ber 25,  1900. 

As  Dr.  Lazear  was  bitten  by  a  mosquito  while  present  in  the  wards 
of  a  yellow-fever  hospital,  one  must,  at  least,  admit  the  possibility  of 
this  insect's  contamination  by  a  previous  bite  of  a  yellow-fever 
patient.  This  case  of  accidental  infection  therefore  can  not  fail  to 
be  of  interest,  taken  in  connection  with  cases  10  and  11. 

For  ourselves,  we  have  been  profoundly  impressed  with  the  mode  of 
infection  and  with  the  results  that  followed  the  bite  of  the  mosquito 
in  these  three  cases.  Our  results  would  appear  to  throw  new  light 
on  Carter's  observations  in  Mississippi,  as  to  the  period  required 
between  the  introduction  of  the  first  (infecting)  case  and  the  occur- 
rence of  secondary  cases  of  yellow  fever. 

Since  we  here,  for  the  first  time,  record  a  case  in  which  a  typical 
attack  of  yellow  fever  has  followed  the  bite  of  an  infected  mosquito, 
within  the  usual  period  of  incubation  of  the  disease,  and  in  which 
other  sources  of  infection  can  be  excluded,  we  feel  confident  that  the 
publication  of  these  observations  must  excite  renewed  interest  in  the 
mosquito  theory  of  the'  propagation  of  yellow  fever,  as  first  proposed 
by  Finlay. 

From  our  study  thus  far  of  yellow  fever,  we  draw  the  following 
conclusions : 

1.  Bacillus  icteroides  (Sanarelli)  stands  in  no  causative  relation  to 
yellow  fever,  but  when  present  should  be  considered  as  a  secondary 
invader  in  this  disease. 

,  The  mosquito  serves  as  the  intermediate  host  for  the  parasite  of     1) 
yellow  fever. 


CHAT  i-  1 
THE  ETIOLOGY  OF  YELLOW  FEVER.—  AN  ADDITIONAL  NOTE.1 

\YAI.TBRREED.'  •••<!  Statee  Ann 

TIDES  AQRAMOMI    M    I>  .  Art  ing  Assistant  Surgeons,  United  States  A  i 

At  the  twent\  -eighth  annual  meeting  of  the  American  Public  I  lealth 

Association,3  held  in  Indianapolis.  End.,  Octoher  I'  _'-_'»;.   P.MMI,  \\e  piv- 

M-nted.  in  the  form  of  a  preliminary  note,  the  results  of  our  bac 
teriologic  study  of  yellow  fever,  based  on  cultures  taken  from  tin'  Mood 
in  18  cases  at  various  stages  of  the  disease,  as  well  as  on  th.»se  which 
we  have  made  from  the  blood  and  organs  of  11  yelh>w-fever  < 
We  also  recorded  the  results  obtained  from  the  inoculation  of  11  non- 
immune  individuals  by  means  of  the  bite  of  mosquit* 

Kabr.)  that  had  previously  fed  on  the  blood  of  patients  sick  with 
yellow  fever.  We  were  able  to  report  two  positive  results.  in  which 
the  attack  of  yellow  fever  followea  the  bite  of  a  mosquito  \\  ithin  the 
usual  period  of  incubation  of  this  disease. 

In  one  of  these  cases  all  other  sources  of  infection  could  !>c  j 
tivclv  excluded.     From  our  several  observations  we  drew  the  follow- 
ing conclusions:  (1)  BadUus  icteroides  (Sanarelli)  stands  in  DO  causa- 
tive relation  to  yellow  fever,  but  when  present  should  be  considered 
as  a  secondary  invader  in  this  disease.     (2)  The  mosquito  sen  e 
the  intermediate  host  for  the  parasite  of  yellow  fever.     Since  t  he  pu  I  >- 
Heat  ion  of  our  preliminary  note  we  have  continued  our  invest  Lr:  i  ions. 
especially  as  regards  the  means  by  which    ellow  fever  is  propagated 

hi 


from  individual  to  individual,  and  as  to  the  manner  hi  which  h> 
become  infected  with  the  contagium  of  this  disease.     The   results 
already  obtained  are  so  positive  and  striking  that,  with  the  permis- 
sion of  Surg.  Gen.  Steinberg,  we  have  concluded  to  present   to  this 
congress  an    additional    note,  in  which  we  will  record  the-e 
observations.     We  desire  to  here  express  our  sincere  thanks  t<>  the 
military  governor  of  the  island  of  Cuba,  Maj.  Gen.  Leonard  \\oo.i. 
United  States  Volunteers,  without  whose  approval  and  assi-tame 
these  observations  could  not  have  been  carriea  out. 

In  order  to  exercise  perfect  control  over  the  movements  of  those 
individuals  who  were  to  be  subjected  to  experimentation,  and  to 
avoid  any  other  possible  source  of  infection,  a  location  was  selected 
in  an  open  and  uncultivated  field,  about  1  mile  from  the  town  of 
Quemados,  Cuba.  Here  an  experimental  sanitary  station  waa  e>iah- 
Ii-hed  under  the  complete  control  of  the  senior  member  of  this  board. 
This  station  was  named  (  'amp  La/ear,  in  honor  of  our  late  colleague, 
Dr.  Jesse  W.  Lazear,  acting  assistant  surgeon,  Tinted  State 
who  died  of  yellow  fever,  while  courageously  investigating  the 

causation  <»f  this  disease.  The  site  selected  was  very  well  drained, 
freely  exposed  to  sunlight  and  winds,  and,  from  every  point  of  \  iew, 
satisfactory  for  the  purpose  intended. 


>  R«d  At  the  Pan  Am.  Med.  Cong.,  held  In  Hftbtna,  Cube,  Feb.  4-7,  1901. 

'1'hllA.lUd.Joir  1900? 

70 


YELLOW   FEVER.  71 

The  personnel  of  this  camp  consisted  of  two  medical  officers,  Dr. 
Roger  r.  Ames,  acting  assistant  surgeon,  United  States  Army,  an 
immune;  in  immediate  charge;  Dr.  R.  P.  Cooke,  acting  assistant 
surgeon,  United  States  Army,  nonimmune;  one  acting  hospital 
steward,  an  immune;  nine  privates  of  the  hospital  corps,  one  of  wnom 
was  immune;  and  one  immune  ambulance  driver. 

For  the  quartering  of  this  detachment,  and  of  such  nonimmune 
individuals  as  should  be  received  for  experimentation,  hospital  tents, 
properly  floored,  were  provided.  These  were  placed  at  a  distance  of 
about  20  feet  from  each  other,  and  were  numbered  1  to  7,  respectively. 

Camp  Lazear  was  established  November  20,  1900,  and  from  this 
date  was  strictly  quarantined,  no  one  being  permitted  to  leave  or 
enter  camp  except  the  three  immune  members  of  the  detachment 
and  the  members  of  the  board.  Supplies  were  drawn  chiefly  from 
Columbia  Barracks,  and  for  this  purpose  a  conveyance  under  the  con- 
trol of  an  immune  acting  hospital  steward,  and  having  an  immune 
driver,  was  used. 

A  few  Spanish  immigrants,  recently  arrived  at  the  port  of  Habana, 
were  received  at  Camp  Lazear,  from  time  to  time,  while  these  observa- 
tions were  being  earned  out.  A  nonimmune  person,  having  once  left 
this  camp,  was  not  permitted  to  return  to  it  under  any  circumstances 
whatever. 

The  temperature  and  pulse  of  all  nonimmune  residents  were  care- 
fully recorded  three  times  a  day.  Under  these  circumstances  any 
infected  individual  entering  the  camp  could  be  promptly  detected  and 
removed.  As  a  matter  of  fact  only  two  persons,  not  the  subject  of 
experimentation,  developed  any  rise  of  temperature;  one,  a  Spanish 
immigrant,  with  probably  commencing  pulmonary  tuberculosis,  who 
was  discharged  at  the  end  of  three  days;  and  the  other,  a  Spanish 
immigrant,  who  developed  a  temperature  of  102.6°  F.  on  the  after- 
noon of  his  fourth  day  in  camp.  He  was  at  once  removed  with  his 
entire  bedding  and  baggage  ana  placed  in  the  receiving  ward  at  Colum- 
bia Barracks.  His  fever,  which  was  marked  by  daily  intermissions 
for  three  days,  subsided  on  the  administration  of  cathartics  and  ene- 
mata.  His  first  attack  was  considered  to  be  due  to  intestinal  irrita- 
tion. He  was  not  permitted,  however,  to  return  to  the  camp. 

No  nonimmune  resident  was  subjected  to  inoculation  who  had  not 
passed  in  this  camg  the  full  period  of  incubation  of  yellow  fever,  with 
one  exception,  to  be  hereinafter  mentioned. 

OBSERVATIONS. 

Having  thus  sufficiently  indicated  the  environment  of  Camp 
Lazear  and  the  conditions  under  which  its  residents  lived,  we  wifi 
now  proceed  to  a  narration  of  the  observations  thus  far  made  at  this 
experimental  station.  At  the  time  these  inoculations  were  begun, 
the  several  tents  were  occupied  as  follows:  Tent  No.  1  by  one  im- 
mune and  one  nonimmune;  No.  2  by  one  immune  and  two  non- 
immunes;  No.  3  by  two  immunes;  No.  4  by  three  nonimmunes; 
No.  5  by  three  nonimmunes;  No.  6  by  two  nonimmunes;  and  No.  7 
by  one  nonimmune. 

For  the  purpose  of  experimentation,  subjects  were  selected  as 
follows:  From  tent  No.  2,  two  nonimmunes,  and  from  tent  No.  5, 
three  nonimmunes.  Later,  one  nonimmune  in  tent  No.  6  was  also 
designated  for  inoculation. 


YKLLOW     I'KVKK. 


7:: 


74  YELU)W 

CM*  /.— Pvt.  John  R.  Kissinger,  Hospital  Corps,  United  States  Army,  aged 
nonimmune,  occupant  of  tent  No.  2,  with  his  full  consent.  was  bitten  ai  10 .:>o  a.  in.. 
November  20,  1900,  by  a  mosquito  (C.  fcuciatut)  that  had  bitten  a  sever 
yellow  fever  on  the  fifth  day,  11  days  previously;  another  severe  case,  on  the  third 
day,  6  days  before;  and  a  third  severe  one  on  the  third  day,  3  days  before.    As  Kissinger 
had  not  absented  himself  from  Columbia  Barracks  for  a  period  of  more  than  30  da 
was  considered  safe  to  inoculate  him  without  waiting  tor  his  period  of  incubation  to 


November  23t  1900,  Kissinger  was  again  bitten  by  the  same  mosquito     The  result 
of  both  inoculations  was  negative.    The  mosquito,  therefore,  was  incapable  • 
ing  any  infection  on  the  eleventh  or  fourteenth  day  after  it  had  bitten  a  severe  case 
of  yellow  fever  on  the  third  day  of  the  disease.    This  insect  had  been  kept  at  .  >n  1 
room  temperature  and  died  November  26.  1900. 

Decembers.  1900.  at  2  p.  m. ,  12  days  after  the  last  inoculation,  Kissinger  was  again 
bitten  by  o  mosquitoes (C.fasciatu*),  2 of  which  had  bitten  fatal  cases  ..f  \«-ll..\\ 
1  the  second  day,  15  days  before:  1  a  severe  case  on  the  second  day,  19  d  i-l\. 

and  2  a  mild  case  on  the  third  day.  21  days  b. 

Thereraixloftemiyratureandpufo.^^ 

showed  that  the  «n tu«v*fr  ^"TMP^fl  IP  flla  1VnUftl  "^te  of  DQMth  dyjipg  ' 
days,  except  that  OP  f><vynnhftrH|  nn  ttift  thit*r day  ~Kia«ingttr  h^/)  BiM^JMMpJflMMI 
rising,  which  soon  passecj  away.     At  4.30  p.  m. — commencement  ot  fourth  foy— -he 
complained  of  frontal  headache;  otherwise  he  felt  well  ami  partook  of  supper  with 
appetite;  at  9  p.  m.,  temperature  was  98.4°  F..  pulse  90;  at  1  !.:;<>  p    m     lie 
with  a  chill,  his  temperature  100°  F.,  pulse  90;  he  complained  of  severe  frontal  head 

jecled   a'l 


ache  ajiorTOc^acn^fnireyeTwere  injecTeTTand  his  fa«  -e  .-uiTui-ed. 

a.  m.,  his  temperature  was  102°^. ,  pulse  102;  he  had  violent  hea 

with  nausea  ana  vomiungi He  was  then  removed  to  the  yell 

subsequent  history  was  that  of  a  case  of  yellow  fever  at  moderat 

appeared  in  the  urine  on  the  fourth  day/im-rea-ed  |,,,,ne-lifth  l. 

day,  and  disappeared  on  December  22.     Granular  casts  were  pr 

numbers'  from  the  fourth  to  the  eighth  day" Th«  ConJVPct4Yff  w 

third  day.    The  diagnosis  of  yellow  fever  in  this  case  was  made  by  Drs 

Carles  Finlay.  \V.  (\  Gorgas,  and  A.  Diaz  All»ertini.  the'board  of  yell 

of  the  city  of  Habana,  who  saw  the  patient  on  several  occasions  during  his  illness. 

Chart  I.)    The  period  of  incul>at  ion  in  this  case  was  3  days,  9J  hours. 

Case  2. — John  J.  Moran,  ag^ed  24,  an  American,  nonimmune,  occupant  «>f  tent 
with  his  full  consent,  was  bitten  at  10  a.  m.,  November  26,  1900,  by  a  m.^,ju; 
faaciatus)  which  12  days  before  had  bitten  a  case  of  yellow  fever  of  moderate  se  , 
on  the  third  day  of  the  disease.    This  insect  had  also  bitten  a  well -marked  case  of 
yellow  fever — second  day — 10  days  previously. 

November  29,  at  2.20  p.  m.,  Moran  was  again  bitten  by  the  same  mosqu 
result  of  both  of  these  inoculations  was  negative.    This  insect  was  the:  pa  Me 

of  conveying  the  infection  15  days  after  having  bitten  a  case  of  yell<.\\  fever  .  i  mod- 
erate severity  on  the  third  day,  and  13  days  after  it  had  liitten  a  well-marked  case  of 
this  disease  on  the  second  day.  This  mosquito  had  been  kept  a  .ture. 

Moran 's  case  will  be  again  referred  to  when  we  come  to  speak  of  the  im 
building  by  means  of  contaminated  mosquitoes. 

CaseS. — A  Spanish  immigrant,  aged  26,  a  nonimmune  occupant  oft  with 

his  full  consent,  was  bitten  at  4  p.  m.,  Decembers,  1900,  by  4  mosquitoes  ( i 
which  had  been  contaminated  as  follows:  One  by  biting  a  fatal  case  of  yel 
on  the  third  day,  17  days  before;  1  a  severe  case,  on  the  third  day,  18  day 
a  severe  case,  on  the  second  day,  22  days  before,  and  1  a  case  of  moderate  -e\erit\ . 
on  the  third  day,  24  days  previously. 

The  record  of  temperature  and  pulse,  taken  every3  hours  after  the  ino<  ulati. m.  >hows 
no  rise  of  temperature  above  99°  F.  until  (i  p.  m..  De.eml.er  l.;   ..n  the  MXII 
when  99.4°  F.  is  recorded;  pulse,  68.    The  Hiibjeet.  who  was  of  a  very  lively  disposi- 
tion, retained  his  usual  spirits  until  noon  of  the  13th,  although  he  complained  oi 
frontal  headache  on  the  llth  and  12th.    He  took  to  his  bea  at  noon  of  the  I ::ih.  the 
fifth  day,  complaining  of  increased  frontal  headache  and  a  sense  of 
p.  m.,  his  temperature  was  98.2°  F.,  pulse  62. 

December  14,  at  6  a.  m.,  temperature  was  98°  F.,  pulse  72,  and  he  still  < 
of  frontal  headache  and  general  malaise.    Profuse  epistaxis  occurred  at  7.45  a.  m. ;  at 
9  a.  m.,  temperature  was  99.6°  F.,  pulse  80;  at  1.15  p.  m.,  temperature  was  100°  F., 


.10  p.  m.,  temperature  juu./-  r .,  pulse  OB;  nis  lace  nusnea  ana  eye- 
removed  to  the  yellow-fever  warns.    A  trace  of  albumin  was  found  in  the  urine 


YELLOW    FEVER.  75 

passed  at  3.30  p.  m.,  December  15;  a  few  hyaline  cases  were  present.  He  was  seen 
at  this  time  by  the  Habana  board  of  experts,  and  the  diagnosis  of  mild  yellow  fever 
confirmed.  (See  Chart  No.  2.) 

The  period  of  incubation  in  this  case  was  4  days  and  24  hours,  counting  from  the 
time  of  inoculation  to  the  hour  when  the  patient  took  to  his  bed;  if  reckoned  to  the 
onset  of  fever,  it  was  5  days  and  17  hours. 

Case  4. — A  Spanish  immigrant,  aged  27,  a  nonimmune  occupant  of  tent  No.  5, 
with  his  full  consent,  was  bitten  at  10  a.  m.  November  26,  1900,  by  a  mosquito  (C. 
fasdatus)  which  had  bitten  a  severe  case  of  yellow  fever  on  the  second  day  10  days 
before.  Three  days  later,  November  29,  he  was  again  bitten  by  the  same  insect. 
December  2,  after  an  interval  of  3  days,  he  was  again  bitten  by  the  same  insect, 
and  also  by  a  second  mosquito  ( C.  fasdatus)  which  12  days  before  had  been  con- 
taminated by  biting  a  fatal  case  of  yellow  fever  on  the  third  day.  No  unfavorable 
effects  followed  any  of  these  attempted  inoculations.  The  first-mentioned  mosquito, 
therefore,  was  incapable  of  conveying  any  infection  on  the  seventeenth  day  after 
biting  a  severe  case  of  yellow  fever  on  the  second  day;  the  other  also  failed  to  infect 
on  the%  twelfth  day  after  biting  a  fatal  case  of  yellow  fever  on  the  third  day.  Both 
of  these  mosquitoes  had  been  kept  at  ordinary  room  temperature. 

December  9,  after  an  interval  of  7  days,  the  subject  was  again  bitten,  at  10.30  a.  m., 
by  1  mosquito  (C.  fasdatus)  which  had  been  infected  19  days  before  by  biting  a 
fatal  case  of  yellow  fever  on  the  second  day  of  the  disease.  He  remained  in  his  usual 
health  until  9  a.  m.  December  12,  the  third  day,  when  he  complained  of  frontal 
headache;  his  temperature  was  98.8°  F.,  pulse  96.  This  headache  continued  during 
the  entire  day.  At  6  p.  m.  temperature  was  99°  F.,  pulse  94;  at  9  p.  m.  tempera- 
ture 99°  F.,  pulse  84;  at  9.30  p.  m.  temperature  99.4°  F.,  pulse  82.  Severe  head- 
ache and  backache  was  complained  of;  his  eyes  were  injected  and  his  face  suffused. 
The  following  morning  he  was  sent  to  the  yellow-fever  wards.  Urine  passed  at  4.20 
p.  m.  December  15,  the  third  day,  gave  a  distinct  trace  of  albumin.  Many  hyaline 
casts  were  present  on  the  same  date.  The  conjunctives  were  jaundiced  on  the  third 
day. 

The  patient  was  seen  by  the  board  of  experts  on  December  14  and  the  diagnosis 
of  yellow  fever  made.  (See  Chart  No.  3.) 

The  period  of  incubation  in  this  case  was  3  days  11$  hours. 

Case  5. — A  Spanish  immigrant,  aged  26,  a  nonimmune  occupant  of  tent  No.  5, 
with  his  full  consent,  was  bitten  at  10  a.  m.  November  26,  1900,  by  a  mosquito  (C. 
fasdatus)  that  had  bitten  a  well-marked  case  of  yellow  fever  on  the  third  day  12 
days  before.  November  29  he  was  again  bitten  by  the  same  insect.  December  2 
he  was  for  the  third  time  bitten  by  2  mosquitoes  (C.  fasdatus),  beth  of  which  had 
bitten  a  well-marked  case  of  yellow  fever  on  the  third  day,  18  days  before.  As  no 
bad  results  followed  any  of  these  inoculations,  it  follows  that  these  mosquitoes  were 
incapable  of  conveying  any  infection  18  days  after  they  had  bitten  a  well-marked 
case  of  yellow  fever  on  the  third  day.  Both  of  these  insects  had  been  kept  at  room 
temperature. 

December  11,  after  an  interval  of  9  days,  the  subject  was  again,  at  4.30  p.  m.,  bitten 
by  the  same  mosquitoes,  4  in  number,  that  had  been  applied  to  case  3  three  days  prior 
to  this  time,  with  positive  results. 

The  record  of  temperature  and  pulse,  taken  every  3  hours  following  the  inoculation, 
showed  no  change  till  December  13,  the  second  day,  at  9  a.  m.,  when  the  temperature 
was  99°  F.,  and  the  pulse  78.  From  this  hour  till  6  p.  m.  the  temperature  varied  from 
99.2°  to  99.6°  F.  The  subject  complained  of  frontal  headache,  slight  in  degree, 
during  the  entire  day.  At  9  p.  m.  his  temperature  was  98.4°  F.,  pulse  62. 

December  14,  the  third  day,  he  complained  of  slight  frontal  headache  during  the 
entire  day,  and  was  indisposed  to  exertion.  From  6  a.  m.  to  6  p.  m.  the  temperature 
averaged  99.2°  F. ,  and  the  pulse  varied  from  64  to  90;  at  9  p.  m.  it  was  98.4°  F. ,  the  pulse 
78.  December  15,  the  fourth  day,  at  6  a.  m.  temperature  was  98.2°  F.,  pulse  78. 
He  still  had  frontal  headache.  At  9  a.  m.  temperature  was  99.2°  F.,  pulse  80;  at  12, 
noon,  the  former  was  99.2°  F.,  the  pulse  74.  The  subject  now  went  to  bed,  complaining 
of  headache  and  pains  throughout  the  body.  At  2  p.  m.  the  temperature  was  100°  F., 
the  pulse  80;  eyes  much  congested;  face  flushed.  At  6  p.  m.  his  temperature  had  risen 
to  102°  F.,  and  the  pulse  to  90.  He  was  then  transferred  to  the  yellow  fever  wards. 
Albumin  appeared  in  the  urine  at  7.30  a.  m.,  December  17.  Bleeding  from  the  gums 
and  roof  of  the  mouth  occurred  on  the  sixth  and  seventh  days  of  his  illness. 

The  case  was  examined  by  the  board  of  experts  on  the  16th  and  19th,  and  the  diag- 
nosis of  yellow  fever  made. 

Albumin  disappeared  on  the  sixth  day,  the  temperature  falling  to  normal  on  this 
date,  and  remaining  near  this  point  till  December  23,  the  ninth  day  of  sickness, 
when  a  relapse  occurred,  attended  with  bleeding  from  the  gums  on  December  24 


YELLOW    FEVER. 


77 


78 


YELLOW 


YELLOW    FEVER. 


79 


80 

and  25,  with  the  appearance  of  red  blood  cells  and  pus  «•«•!!<  in  tho  urine  in  moderate 
numbere.  Fevereuoeided  on  December  26,  and  the  urine  became  normal  on  Decemlu>r 
29.  (See  Chart 

The  period  of  incubation  in  this  case,  if  reckoned  from  the  time  of  inoculation  to 
the  hour  when  the  patient  took  to  his  bed,  was  3  days,  19$  hours. 

The  four  patients  whoso  histories  we  have  above  w. 

examined_by  anumbcr  «»f  ph\  --iciansof  II  .unong  v  may 


mention  uf<>.  <>f  '        '  Dr.  S;;  of  "La  1> 

fica,'1  and  J>r.  Moas.  of  "La   1'n;  all  of  \\honi 

the  diagnosis  of  yellow  fever  >yas  confirmed.     :  rapidly 

revie  instances  an  end  i-  d  yellow 

fever,  in  order  to  emph.-i-  be  of  interest  and  im: 

nnection  with  tfieir  occurrence.     (\Ve  omit  any  o  the 

clinical  histories.) 

It  should  he  borne  in  mind  that  at  the  time  when  these  inoculations 

:m  there  were  only  l'J  nouimmune  n  < 

and  that  5  of  tlu^e  v.  !>e;-imeir 

and  3  in  tent  No.  5.     Of  thoo  \\e  succeeded  in  infecting    1.  vi/.,  1  in 
lent  No.  2  and  :>  in  tent  No.  A.  each  of  whom  developed  .  ,-k  of 

yellow  fever  within  the  period  of  incubation  of  this  disease.     The  on€ 
negative  result,  therefore,  A\  -e  2 — Moran — inoculated  \\  i 

mosquito  on  the  fifteenth  day  after  the  insect   had  ->o  of 

yellow  fever  on  the  third  day.     Since  this  moscjuito  failed  to  infect 
case  4,  three  days  after  it  had  hit  ten  Moran,  it  follow-  th;it  the  ; 
could  not  have  been  otherwise  than  negative  in  the  !  We 

now  know,  as  the  result  of  our  observations,  that  in  the  case  of  an 
i  kept  at  room  temperature  during  the  cool  weal  her  of  November. 
15  or  even  18  days  would,  in  all  probability,  be  too  short  a  tin 
render  it  capable  of  producing  the  disease. 

As  bearing  on  the  source  of  infection,  we  invite  attention  to  the 
period  of  time  during  which  the  subjects  had  been  kept   under  riirid 
quarantine,  prior  to  successful  inoculation,  which  was  as  foli 
Case  1,  15  days;  case  3,  9  days;  case  4,  19  da 

We  further  desire  to  emphasize  the  fact  that  this  epidemic  of  yellow 
fever,  which  affected  33.33  per  cent,  of  the  nonimmune  resident 
(amp  Lazear,  did  not  concern  the  7  nonimmun«'s  occupying  ' 
No.  1,  4,  6,  and  7,  but  was  strictly  limited  to  th«><e  individuals  who 
had  been  bitten  by  contaminated  mosquitoes. 

Nothing  could  point  more  forcibly  to  the  source  of  this  infection 
than  the  order  of  the  occurrence  of  events  at   this  camp.     The 
cision  with  which  the  infection  of  the  individual  followed  the  hi 
the  mosquito  left  nothing  to  be  desired  in  order  to  fulfill  the  require- 
ments or  a  scientific  experiment. 

The  epidemic  having  ceased  on  December  I.",  r.uui.  no  other  case 
of  vellov.  occurred  in  this  camp  until  we  again  began  i 

individuals  to  inoculation.     Thus  lo  day-  later  \\e  made  t  he  i<>!lo\\  ing 
observation: 

Cote  6. — A  Spanish  immigrant,  aged  27,  a  nonimmune  oocupam 
his  full  consent,  was  bitten  at  11  a.  in  .  I  :;0,  1900,  by  4  mosquitoes  (C  fascia- 

tiis)  that  had  been  contaminated  17  days  pn-vi-m.-ly  I  mild  case  of  yellow 

on  the  fust  day  of  the  disease  (case  4).    These  insects  had  been  kept  at  a  tem- 
jMTaturo  of  S2°  1 

-•inaincd  in  hi-  normal  condilion  until  the  P\«  !'»()!. 

the  third  day,  when  he  complainH  of  frontal  h< -a-l a-  !]••       \t  «i  j>. 
wa«990F.,  pub*e64.     ll>  Lbutniill-  d  of  headache  on  the  foil 

II"  partook  sparingly  of  breakfast,  and  afterwards  lay  < 


YELLOW   FEVER.  81 

being  disinclined  to  exert  himself.  At  9  a.  m.,  the  temperature  was  99°  F.,  the  pulse 
96;  at  10.30  a.  m.,  temperature  100°  F.,  pulse  80.  A  sense  of  chilliness  and  sharp 
frontal  headache  was  complained  of,  and  at  3  p.  m.  his  temperature  was  100.8°  F.,  his 
pulse  89,  and  his  eyes  were  congested  and  face  flushed.  He  was  removed  to  the 
yellow-fever  wards.  A  specimen  of  urine  passed  at  midnight,  January  4,  contained  a 
distinct  trace  of  albumin.  Slight  bleeding  from  the  gums  occurred  on  the  fifth  and 
sixth  days.  The  patient  was  seen  by  the  board  of  experts  on  the  second  and  seventh 
days  of  his  attack,  and  the  diagnosis  of  yellow  fever  confirmed.  (See  Chart  5.) 

The  period  of  incubation  in  this  case  was  3  days.  22£  hours.  The  subject  had 
remained  in  strict  quarantine  for  22  days  preceding  his  inoculation. 

In  considering  the  character  of  the  attacks  and  the  course  of  the 
disease  in  these  five  cases  of  experimental  yellow  fever,  it  must  be 
borne  in  mind  that  these  infected  individuals  were  all  young  men,  in 
good  general  physical  condition  and  placed  amid  excellent  hygienic 
surroundings.  Further,  it  must  not  be  forgotten  that,  on  the  earliest 
manifestation  of  an  approaching  infection,  they  were  each  and  all  put 
to  bed  at  once,  and  were  even  carried  to  the  yellow-fever  wards  while 
occupying  the  same  bed.  In  other  words,  these  men  were  kept  at 
absolute  rest  from  the  first  inception  of  the  disease.  Just  what  bear- 
ing this  may  have  had  on  the  subsequent  course  of  the  fever,  we  can 
not  say,  but  since  so  much  stress  is  laid  on  absolute  rest  of  the  patient 
by  those  having  most  experience  in  the  treatment  of  yellow  fever,  the 
influence  of  this  enforced  rest,  in  our  case,  upon  the  subsequent 
course  of  the  attack,  was  doubtless  of  much  importance.  We  reserve 
a  consideration  of  the  clinical  side  of  these  cases  for  a  future  report. 

In  our  opinion,  the  experiments  above  described  conclusively 
demonstrate  that  an  attack  of  yellow  fever  may  be  readily  induced 
in  the  healthy  subject  by  the  bite  of  mosquitoes  (C.fasciatus)  which 
have  been  previously  contaminated  by  being  fed  with  the  blood  of 
those  sick  with  yellow  fever,  provided  the  insects  are  kept  for  a  suffi- 
cient length  of  time  after  contamination  before  being  applied  to  the 
person  to  be  infected. 

Our  observations  do  not  confirm  Finlay's  statement  that  the  bite 
of  the  mosquito  may  confer  an  abortive  attack  of  yellow  fever  when 
applied  to  the  healthy  subject  2  to  6  days  after  it  has  bitten  a  yellow 
fever  patient.  We  have  always  failed  to  induce  an  attack  even  of 
the  mddest  description  when  we  have  used  mosquitoes  within  less 
than  12  days  from  the  time  of  contamination,  although  the  insects 
were  constantly  kept  at  summer  temperature.  We  could  cite 
instances  where  we  have  applied  mosquitoes  at  intervals  of  2,  3,  4, 
5,  6,  9,  and  11  days  following  the  contamination  of  the  insect  with 
the  blood  of  well-marked  cases  of  yellow  fever  early  in  the  disease 
without  any  effect  whatever  being  produced  by  the  bite.  Thus  in  1 
case  no  result  followed  the  bite  of  14  mosquitoes  which  4  days  pre- 
viously had  been  contaminated  by  biting  a  case  of  yellow  fever  on 
the  first  day.  Again,  7  days  later,  or  11  days  after  contamination, 
the  surviving  7  of  these  insects  failed  to  infect  an  individual.  On 
the  seventeenth  day  after  contamination,  however,  the  bite  of  4  of 
these  mosquitoes — all  that  remained  of  the  original  14 — was  promptly 
followed  by  an  attack  of  yellow  fever  in  the  same  individual.  These 
insects  had  been  kept  during  the  whole  of  this  time  at  an  average 
temperature  of  82°  F. 

Our  observations  would  seem  to  indicate  that  after  the  parasite 
has  been  taken  into  the  mosquito's  stomach,  a  certain  number  of 
days  must  elapse  before  the  insect  is  capable  of  reconveying  it  to  man. 

79965°— S.  Doc.  822,  61-3 6 


82 

This  period  doubtless  represent*  the  time  required  for  the  i>ara*ite 
to  pass  from  the  inaect'fl  stomach  to  it<  salivary  glands,  ana  would 

appear  to  be  about   1  in  summer  weather  and  moM    probably 

about  18  or  more  days  during  the  cooler  \\inter  months  It  follows 
also  that  our  ohs,«r\  at  i«>n-  do  n«t  cnnlirm  Kinlay'*  opinion  that  the 
bite  of  the  contaminated  mosquito  may  confer  immum  isl  a 

subsequent  attack  of  \ell..\\  In  our  experience  an  individual 

mav  he  hit  ten  on  three  or  more  occasions  by  contaminated  moM|ii 
\\itliout  manifesting  an\   BJ  mptoms  of  di-t  urbancc  to  health,  and  yet 
promptly  si, -ken    \\ith    yellow  fever   within    a    fe\\    day-    after   being 
hitten  by  an  in-cct  capahle  of  coim-yini:  the  infection. 

IKIMI.N  i    «u     mi:    in-KASE. 

Having  shown   that    yellow  fever    can    he    conveyed    hy   the   hite  of 
an   infected   mosquito,   it    remain-    to   inquire    whether   this   disease 
can  be  acquired  in  any  other  manner.     It  has  seemed   to  us   that 
vellow  fever,  like  the  several  types  of  malarial  fever,  might  he  ind 
'hy    the   injection   of  blood    taken    from   the   general   circulation 
natient  sull'ering  from  this  disease.     Accordingly  we-  have  subj. 
tour  individuals  to  this  method  of  infection,  with  one  i  and 

three  positive   results.      Reserving  the  detailed   description   of    • 
cases  to  a  subsequent  occasion,  we  may  state  that  in  one  of  the  ; 
live  cases  an  attack  of  pronounced  yellow  fever  followed  the  >ul>< -u- 
taneous  injection  of  2  c.  c.  of  blood  taken  from  a  vein  at  the  bend  of 
the  elbow  on  the  first  day  of  the  disease,  the  period  of   incubation 
being  3  days  and  22  hours;  in  the  second  case,  1.5  c.  c.  of  blood,  t  aken 
on  the  first  day  of   the  disease    and  injected  in  the  same  manner, 
brought  about  *an  attack  within  2  days  and  12  hours:  while  in  our 
third  case,  the  injection  of  0.5  c.  c.  of  blood,  taken  on  the  second  day 
of  the  disease,  produced  an  attack  at  the  end  of  41  hours. 

In  the  case  mentioned  as  negative  to  the  blood  injection,  the  .sub- 
sequent inoculation  of  this  individual  with  mosquitoes  already  pi 
to  oe  capable  of  conveying  the  disease,  also  resulted  negat  ively.  \\V 
think,  therefore,  that  this  particular  individual,  a  Spanish  immigrant, 
may  be  considered  as  one  who  probably  possesses  a  natural  immunity 
to  yellow  fever. 

It  is  important  to  note  that  in  the  three  cases  in  which  the  injection 
of  the  blood  brought  about  an  attack  of  yellow  fever,  careful  cultures 
from  the  same  blood,  taken  immediately  after  injection,  failed  to 
show  the  presence  of  Sanarelli's  bacillus.1 

Our  observations,  therefore,  show  that  the  parasite  of  yellow  fever 
i-  present  in  the  general  and  capillary  circulation,  at  least  during  the 
early  stages  of  this  disease,  and  that  the  latter  may  be  conveyed,  like 

nalarial  parasite,  either  hy  means  of  the  hite  of  the   moxpii' 
by  the  injection  of  blood  taken  from  the  general  circulation. 

1  A  fourth  case  tf  yellow  fever,  severe  in  type,  has  been  produced  by  the  subcutaneous  injection  • 
of  blood  taken  from  the  general  circul .  eoond  day  of  the  disease,  the  period  < 

3  days  and  1  hour.    The  patient  from  whom  the  blood  was  obtained  was  an  experimental  case  which  was 
in  turn  produced  bv  the  Injection  of  blood— 0.5  c.  c.— derived  from  a  nonexpert 
fever.    As  "controls,"  oases  1,  4,  0,  and  7  of  this  report  were  also  injected  subcutaneous  I  y  v. 
the  Mine  blood  without  manifesting  any  symptoms  whatever.    The  blood  which  produced  this 
ca^e  of  yellow  fever,  when  transferred  at  the  same  time  to  bouillon  >u  bes  In  considerable  quantities,  gave  no 
growth  whatever. 


YELLOW  FEVER.  83 

CAN  YELLOW  FEVER  BE  PROPAGATED  IN  ANY  OTHER  WAY  ? 

We  believe  that  the  general  consensus  of  opinion  of  both  the  medical 
profession  and  the  laity  is  strongly  in  favor  of  the  conveyance  of 
yellow  fever  by  fomites.  The  origin  of  epidemics,  devastating  in 
their  course,  has  been  frequently  attributed  to  the  unpacking  of 
trunks  and  boxes  that  contained  supposedly  infected  clothing;  and 
hence  the  efforts  of  health  authorities,  both  State  and  National,  are 
being  constantly  directed  to  the  thorough  disinfection  of  all  clothing 
and  bedding  shipped  from  ports  where  yellow  fever  prevails.  To 
such  extremes  have  efforts  at  disinfection  been  carried,  in  order  to 
prevent  the  importation  of  this  disease  into  the  United  States,  that 
during  the  epidemic  season  all  articles  of  personal  apparel  and  bedding 
have  been  subjected  to  disinfection,  sometimes  both  at  the  port  of 
departure  and  at  the  port  of  arrival;  and  this  has  been  done  whether 
the  articles  have  previously  been  contaminated  by  contact  with 
yellow  fever  patients  or  not.  The  mere  fact  that  the  individual  has 
resided,  even  for  a  day,  in  a  city  where  yellow  fever  is  present,  has 
been  sufficient  cause  to  subject  his  baggage  to  rigid  disinfection  by 
the  sanitary  authorities. 

To  determine,  therefore,  whether  clothing  and  bedding,  which 
have  been  contaminated  by  contact  with  yellow  fever  patients  and 
their  discharges,  can  convey  this  disease  is  a  matter  of  the  utmost 
importance.  Although  the  literature  contains  many  references  to 
the  failure  of  such  contaminated  articles  to  cause  the  disease,  we  have 
considered  it  advisable  to  test,  by  actual  experiment  on  nonimmune 
human  beings,  the  theory  of  the  conveyance  of  yellow  fever  by 
fomites,  since  we  know  of  no  other  way  in  which  this  question  can 
ever  be  finally  determined. 

For  this  purpose  there  was  erected  at  Camp  Lazear  a  small  frame 
house  consisting  of  one  room  14  by  20  feet,  and  known  as  " Building 
No.  1"  or  the  "Infected  clothing  and  bedding  building."  The  cubic 
capacity  of  this  house  was  2,800  feet.  It  was  tightly  ceiled  within 
with  "tongue  and  grooved"  boards,  and  was  well  battened  on  the 
outside.  It  faced  to  the  south  and-  was  provided  with  two  small 
windows,  each  26  by  34  inches  in  size.  These  windows  were  both 
placed  on  the  south  side  of  the  building,  the  purpose  being  to  prevent, 
as  much  as  possible,  any  thorough  circulation  of  the  air  within  the 
house.  They  were  closed  by  permanent  wire  screens  of  0.5  mm. 
mesh.  In  addition  sliding  glass  sash  were  provided  within  and  heavy 
wooden  shutters  without ;  the  latter  intended  to  prevent  the  entrance 
of  sunlight  into  the  building,  as  it  was  deemed  undesirable  that  the 
disinfecting  qualities  of  sunlight,  direct  or  diffused,  should  at  any 
time  be  exerted  on  the  articles  of  clothing  contained  within  this  room. 
Entrance  was  effected  through  a  small  vestibule,  3  by  5  feet,  also 
placed  on  the  southern  side  of  the  house.  This  vestibule  was  pro- 
tected without  by  a  solid  door  and  was  divided  in  its  middle  by  a 
wire  screen  door,  swung  on  spring  hinges.  The  inner  entrance  was 
also  closed  by  a  second  wire  screen  door.  In  this  way  the  passage 
of  mosquitoes  into  this  room  was  effectually  excluded.  During 
the  day,  and  until  after  sunset,  the  house  was  kept  securely  closed, 
while  by  means  of  a  suitable  heating  apparatus  the  temperature  was 
raised  from  92°  to  95°  F.  Precaution  was  taken  at  the  same  time  to 
maintain  a  sufficient  humidity  of  the  atmosphere.  The  average 


84  YELLOW    FEVEB. 

temperature  of  this  house  was  thus  kept   at   76.2°   K.  for  a  period 
of  63  days. 

November  .'U).   I'MHt.  the  building  now  being  ready  for  occupancy. 
three  large  boxes  filled  \\i\\\  sheets,  pillow  slips,  hlankt  con- 

taminated by  contact  with  rases  of  yelh 
were  rec  :id  placed  th-  >   of  tin- 

been  taken  from  the  beds  of  patients  sick  with 
Animas  Hospital,  Ilabana,  or  at  Columbia  Barm  •  hem 

had    hecii   purposely   soiled   with   a   liberal   quantity   of  black   vomit, 
urine,   and   fecal  matter.     A  dirty   "  comfortable"   and   muc!i-M>ilcd 
of  blankets,  removed  from  the  bed  of  a  patient  sick  \\\\\\  yellow 
:  in  the  to\\  n  of  Quemados,  were  contained  in  one  of  these  Do 
The  same  day,  at  6  p.  m.,  Dr.  R.  P.  Cooke.  a<  1 1  mt  sm 

United  States  Army,  and  two  privates  of  the  Hospital  Corps,  all  ; 
immune   young   Americans,    entered    this    building    and    dc! 
unpacked'  these  boxes,  which  had  been  tightly  cl 
a  period  of  two  weeks.     Thev  were  careful  at   the  same  tim 
each  article  a  thorough  handling  and  shaking  in  onl 
through  the  air  of  the  room  the  specific  agent  of  yell 
tained    in   these   fomites.     These   soiled    sheets.    nillo\\ 
blankets  were  used  in  preparing  the  beds  in  which  the  me 
the  Hospital  Corps  slept.     Various  soiled  artiel.  >und 

the  room  and  placed  about  the  bed  occupied  by  Dr. 

From  this  date  until  December  19,  1900,  a  series  of  'J  ihis 

room  was  occupied  each  night  by  these  three  nonimmunes.      ! 
morning  the  various  soiled  articles  were  carefully  packed  in  the  ai 
said  boxes,  and  at  night  again  unpacked  and  distributed  about  the 
room.     During  the  day  the  residents  of  this  house  were  permit  t . 
occupy  a  tent  pitched  in  the  immediate  vicinity,  but  were  kept   in 
strict  quarantine. 

December  12,  a  fourth  box  of  clothing  and  bedding  v  ived 

from  Las  Animas  Hospital.     These  articles  had  been  UMM|  on  the  beds 
of  yellow-fever  patients,  but  in  addition  had  been  pur;  >iled 

with  the  bloody  stools  of  a  fatal  case  of  this  disea  box 

had  been  packed  for  a  number  of  days,  when  opened  and  unpa 
by  Dr.  Cooke  and  his  assistants,  on 'December  1J.  the  odor  \\ 
offensive  as  to  compel  them  to  retreat  from  the  hou>e.     They  piuckilv 
returned,  however,  within  a  short  time  and  spent  tl 

December  19,  these  three  nonimmunes  were  placed  in  quarantine 
for  5  days  and  then  given  the  liberty  of  the  camp.     All  I,  med 

in  perfect  health,  notwithstanding  their  stay  of  20  nigh 
unwholesome  surroundings. 

During  the  week,  December  20- -7.  the  following  articles  were  also 
placed  in  this  house,  viz:  Pajama  suits,  1  :  under>hii 
4;  pillow  slips,  4;  sheets,  6;  bl;,  5;  pillov 

These  article-  had  been  removed  from  the  perx.ns  and  bed-  of  four 
patients  sick  with  yellow   fe\er  and   were   \  ery   much   soiled,   a-- 
change  of  clothing  or  bed  linen  during  their  attacks  had   been   pur- 
posely avoided,  the  object   bein^  to  obtain   articles  as  thoroi: 
contaminated  as  possible. 

om  December  21,  1900,  till  January  10,  1901.  this  building  was 
again  occupied  by  two  noninunune  youn  under  i 

conditions  as  the  preceding  occupants,  except  that  these  men  slept. 


YELLOW   FEVER.  85 

every  night  in  the  very  garments  worn  by  yellow-fever  patients 
throughout  their  entire  attacks,  besides  making  use  exclusively  of 
their  much-soiled  pillow  slips,  sheets,  and  blankets.  At  the  end  of 
21  nights  of  such  intimate  contact  with  these  fomites,  they  also  went 
into  quarantine,  from  which  they  were  released  5  days  later  in  per- 
fect health. 

From  January  11  till  January  31,  a  period  of  20  days,  "Building 
No.  1"  continued  to  be  occupied  by  two  other  nonimmune  Amer- 
icans, who,  like  those  who  preceded  them,  have  slept  every  night  in 
the  beds  formerly  occupied  by  yellow-fever  patients  and  in  the  night- 
shirts used  by  these  patients  throughout  the  attack,  without  change. 
In  addition,  during  the  last  14  nights  of  their  occupancy  of  this  house, 
they  have  slept,  each  night,  with  their  pillows  covered  with  towels 
that  had  been  thoroughly  soiled  with  the  blood  drawn  from  both  the 
general  and  capillary  circulation,  on  the  first  day  of  the  disease,  in 
the  case  of  a  well-marked  attack  of  yellow  fever.  Notwithstanding 
this  trying  ordeal,  these  men  have  continued  to  remain  in  perfect 
health. 

The  attempt  which  we  have  therefore  made  to  infect  "Building 
No.  1  "  and  its  7  nonimmune  occupants,  during  a  period  of  63  days, 
has  proved  an  absolute  failure.  We  think  we  can  not  do  better  here 
than  to  quote  from  the  classic  work  of  La  Roche.1  This  author  says: 

In  relation  to  the  yellow  fever,  are  find  so  many  instances  establishing  the  fact  of  the 
nontransmissibliity  of  the  disease  through  the  agency  of  articles  of  the  kind  mentioned, 
and  of  merchandise  generally,  that  we  can  not  but  discredit  the  accounts  of  a  contrary 
character  assigned  in  medical  writings,  and  still  more  to  those  presented  on  the  strength 
of  popular  report  solely.  For  if  in  a  large  number  of  well  authenticated  cases  such 
articles  have  been  handled  and  used  with  perfect  impunity — and  that,  too,  often  under 
circumstances  best  calculated  to  insure  the  effect  in  question — we  have  every  reason 
to  conclude  that  a  contrary  result  will  not  be  obtained  in  other  instances  of  a  similar 
kind,  and  that  consequently  the  effect  said  to  have  been  produced  by  exposure  to  tnose 
articles  must — unless  established  beyond  the  possibility  of  doubt — be  referred  to  some 
other  agency. 

The  question  here  naturally  arises:  How  does  a  house  become 
infected  with  yellow  fever  ?  This  we  have  attempted  to  solve  by 
the  erection  at  Camp  Lazear  of  a  second  house,  known  as  "Building 
No.  2,"  or  the  "Infected  mosquito  building.''  This  was  in  an 
respects  similar  to  "Building  No.  1,"  except  that  the  door  and 
.windows  were  placed  on  opposite  sides  of  the  building  so  as  to  give 
through-and-through  ventilation.  It  was  divided,  also,  by  a  wire- 
screen  partition,  extending  from  floor  to  ceiling,  into  two  rooms, 
12  by  14  feet  and  8  by  14  feet,  respectively.  Whereas,  all  articles 
admitted  to  "Building  No.  1"  have  been  soiled  by  contact  with 
yellow-fever  patients,  all  articles  admitted  to  "Building  No.  2"  were 
first  carefully  disinfected  by  steam  before  being  placed  therein. 

On  December  21,  1900,  at  11.45  a.  m.,  there  were  set  free  in  the 
large  room  of  this  building  15  mosquitoes  (O.fasciatus)  which  had 
previously  been  contaminated  by  biting  yellow -fever  patients,  as 
follows:  One,  a  severe  case,  on  the  second ^day,  November  27,  1900, 
24  days;  3,  a  well-marked  case,  on  the  first  day,  December  9,  1900, 
12  days;  4,  a  mild  case,  on  the  first  day,  December  13,  1900,  8  days; 
7,  a  well-marked  case,  on  Mie  first  day,  December  16,  1900,  5  days — 
total,  15. 

iR.  La  Roche:  Yellow  Fever,  Vol.  II,  p.  516,  Philadelphia. 


86 

Only  one  of  these  in-«-  idered  capable  of  conveying  the 

infection,  vi/.  the  mosquito  that  had  bitten  a  se\  ere  case  -1  days 
before,  while  3  others — tin*  U-day  inseets--had  possibly  reached  the 
dangerous  stage,  as  thev  had  been  kept  at  an  average  temperature 

At    U   M.  of  the  same  day.  .l«»lm  .1.    Moran     already   referred    to 
186  -  in   this  report,  a  nonimmnne  American,  entered  the  room 
where    the    mo^jtiitn^    had    heen    freed    and    remained    .SO    minute. 
During  this  time  lie  was  hit  ten  about   the  fa  -e  and  hands  b; 

0  p.  in.,  the  same  day.  he  ntered  and  remained 

•JO  minutes,  and  was  again  bitten.     The  followin  >,  m.. 

he,  for  the  third  time,  entered  the  room  and  was  again  bitten. 

Ca*e7.— -On  1'  25.  1900,  at  6  a.  m.,  the  fourth  day.  M..ran  .  ..m|. I. lined  of 

slight  dizziness  and  frontal  headache.     At   II  a.  in.  ho  went  to  bed,  complain 
increased  headache  and  malaiae,  with  ft  temperature  of  99.6°  I-'..  pulse  88;  at  no 
.temperature  was  100.1°  F..  the  pulse  98;  at  1  p.  m.,  101.2°  F..  ih<-  j«  ttd  his 

eyes  were  much  injected  and  face  suffused.     He  was  removed  t»  ih«-  y«-ll..\v 
wards.     He  was  seen  on  several  occasions  by  the  board  of  experts  and  the  diagnosis  of 
ycll<.\v  fryer  confirmed.     (See  Chart  6.) 

The  period  of  incubation  in  this  case,  dating  from  the  first  vi>ii  to 
"Building  No.  2,"  was  3  days  and  23  hours.  If  reckoned  from  his 
last  visit  it  was  2  days  and  18  hours.  Then*  was  no  other  possible 
source  for  his  infection,  as  he  had  been  strictly  (piarantined  at  Camp 
Lazear  for  a  period  of  32  days  prior  to  his  exposure  in  the  mosquito 
building. 

During  each  of  Moran's  visits,  two  nonimmunee  remained  in 
same  buSdinjr,  only  protected  from  the  mosquitoes  by  i  be  \\  ire-eci 
partition.     From  December  21,  1900,  till  January  8,  1901,  inclusive 
18  nights — these  nonimmunes  have  slept  in  this  house,  only  pi 
by  the  wire-screen  partition.     These  men  have  remained  in  perfect 
health  to  the  present  time. 

December  'JS  after  an  interval  of  7  days,  this  house  was  a^ain 
entered  by  a  nonimmune  American,  who  remained  •_!.">  minutes.     The 
subject  was  bitten  by  only  one  insect.     The  following  day  he  a 
entered   and  remained   15  minutes,   and   was  apiiu    bitten    by 
mosquito.     The  result  of  these  two  visits  was  entirely  n  As 

the  mortality  among  the  insects  in  this  room,  from  some  unknown 
cause,  had  been  surprisingly  lanjv.  it  i-  po>-ible  that  tln'Mihjeci 
bitten  by  insects  not  more  than  13  days  old, in  which  case  they  would 
probably  not  infect,  since  they  had  been  kept  for  only  ">  days  at  a  tem- 
perature of  82°  F.,  and  for  8  days  at  the  mean  temperature  ,,f  the 
room,  78°  F. 

Be  this  as  it  may,  nothing  can  be  more  .striking  or  in>tructivo  as 
bearing  upon  the  cause  of  house  infection  in  yellow  fever  than  when 
we  contrast  the  results  obtained  in  our  attempts  to  infect   Buildings 
No.  1   and  No.   2j  for  whereas    in  the    former    all    of    7    nnnimm 
escaped  the  infection,  although  <•  to  the  most  intimate  contact 

with  the  fomites  for  an  aver;i  d  of  21    night  inthel 

an  (••  kerned  by  as  many  minutes,  was  quite  sull'n-ient    to 

give  an  attack  of  yellow  rever  to  one  out  of  two  persons  who  entered 
the  building  ."(•  pel  cent. 

Thus,  at  Camp  La/ear,  of  7  nonimmunes  whom  we  attempted  to 
infect  by  means  of  the  bites  of  contaminated  mosquitoes,  \\e  have 
succeeded  in  conveying  the  di case  to  6,  or  85.71  per  cent.  On  the 


YELLOW    FEVER.  87 

other  hand,  7  nonimmunes  whom  we  tried  to  infect  by  means  of 
fomites,  under  particularly  favorable  circumstances,  We  did  not 
succeed  in  a  single  instance.  Out  of  a  total  of  18  nonimmunes  whom 
We  have  inoculated  with  contaminated  mosquitoes  since  we  began 
this  line  of  investigation,  8,  or  44.4  per  cent,  have  contracted  yellow 
fever.  If  we  exclude  those  individuals  bitten  by  mosquitoes  that 
had  been  kept  less  than  12  days  after  contamination,  and  which  Were, 
therefore,  probably  incapable  of  conveying  the  disease,  we  have  to 
record  8  positive  and  2  negative  results — 80  per  cent. 

CONCLUSIONS. 

1.  The  mosquito  (C.  fasciatus]  serves  as  the  intermediate  host  for 
the  parasite  of  yellow  fever. 

2.  Yellow  fever  is  transmitted  to  the  nonimmune  individual  by 
means  of  the  bite  of  the  mosquito  that  has  previously  fed  on  the 
blood  of  those  sick  with  this  disease. 

3.  An  interval  of  about   12   days  or  more   after  contamination 
appears  to  be  necessary  before  the  mosquito  is  capable  of  conveying 
the  infection. 

4.  The  bite  of  the  mosquito  at  an  earlier  period  after  contamina- 
tion does  not  appear  to  confer  any  immunity  against  a  subsequent 
attack. 

5.  Yellow  fever  can  also  be  experimentally  produced  by  the  sub- 
cutaneous injection   of   blood   taKen   from   the   general   circulation 
during  the  first  and  second  days  of  this  disease. 

6.  An  attack  of  yellow  fever,  produced  by  the  bite  of  the  mosquito, 
confers  immunity  against  the  subsequent  injection  of  the  blood  of  an 
individual  suffering  from  the  nonexperimental  form  of  this  disease. 

7.  The  period  of  incubation  in  13  cases  of  experimental  yellow 
fever  has  varied  from  41  hours  to  5  days  and  17  hours. 

8.  Yellow  fever  is  not  conveyed  by  fomites,  and  hence  disinfection 
of  articles  of  clothing,  bedding,  or  merchandise,  supposedly  contam- 
inated by  contact  with  those  sick  with  this  disease,  is  unnecessary. 

9.  A  house  may  be  said  to  be  infected  with  yellow  fever  only  when 
there  are  present  within  its  walls  contaminated  mosquitoes  capable 
of  conveying  the  parasite  of  this  disease. 

10.  The  spread  of  yellow  fever  can  be  most  effectually  controlled 
by  measures  directed  to  the  destruction  of  mosquitoes  and  the  pro- 
tection of  the  sick  against  the  bites  of  these  insects. 

11.  While  the  mode  of  propagation  of  yellow  fever  has  now  been 
definitely  determined,  the  specific  cause  of  this  disease  remains  to  be 
discovered. 

DISCUSSION. 

Dr.  Louis  Perna,  Cienfuegos,  Cuba,  in  opening  the  discussion,  said 
that  it  is  sophism  to  believe  that  post  hoc,  ergo  propter  hoc;  that  is  to 
:say,  that,  as  Carmona,  Freire,  banarelli,  and  others  have  fallen  to 
this  error,  we  must  not  be  too  precipitate  in  accepting  the  result 
'of  statistics.  The  studies  made  of  mosquitoes  are  very  old.  A 
French  physician,  who  died  about  1850,  expressed  the  opinion  that 
malaria,  yellow  fever,  and  cholera  were  propagated  by  mosquitoes. 
Dr.  Perna  also  criticized  the  methods  employed  by  the  commission 


88 

in  making  experiments  on  human  beings  and  is  entirely  .  >pj>o>ed  to 
aud 

Dr.  San  Mai'tin  eloquently  defended,  and  with  strong  arguments, 
the  high  scientific  standard  of  the  expeiimei  iried  out  by  this 

commission,  and  also  brought  out  the  point  that  it  was  not  stati 
but  facts  that  this  commission  presented. 

Or.  II.  B.  lloilbeck.  Charleston.  S.  ( '  .  expressed  hi-  opinion  that 
the  problem  of  200  years  was  about  to  be  solved,  that  the  old  quar- 
antine regulations  should  be  greatly  modified.  He  al  ibed 
the  «  e  of  a  pine  belt  Within  a  short  distance  of  Charleston. 
S.  C.,  ill  which  yellow  fever  never  developed  as  an  epidemic,  although 
the  afllicted  therewith  would  go  there  during  the  existence  of  the 
epidemic  in  Charleston,  would  die  from  the  disease,  and  \ «  t  it  \\nuld 
not  spread.  Mosquitoes  are  not  known  in  that  region,  and  probably 
this  is  the  true  cxph.nat  ion  of  the  above  fact.  Me  concluded  by 
emphasizing  the  inestimable  value  of  these  cxpeiimcnts  if  they  i 
to  be  true. 

Dr.  Emilio  Marline/..  Ilabana,  laid  emphasis  nn  Dr.  San  Martin's 
V10W8,  lbv  took  up  the  moral  question  and  claimed  that  \\ithout 
these  no  truth  could  have  been  found. 

Dr.  Manuel  (iutierre/..  Mexico,  who  up  to  within  a  short  time  had 
been  adverse  to  the  theory  of  the  transmission  of  this  di-c;:-e  by 
mosquitoes,  now  accepted  as  incontrovertible  the  results  of  the  experi- 
ments of  the  commission.  He  followed  with  interest  many  of  the 
experiments,  and  as  a  member  of  the  commission  saw  n 
cases,  which  he  had  no  hesitation  in  pronouncing  typical  ca-« 
yellow  fever.  A  fact  which  impressed  him  forcibly  was  the  absolute 
control  of  the  epidemic  by  Dr.  Reed.  The  cases  would  develop  or 
not,  as  he  wished.  He  does  not  think  that  the  mosquito  should  be 
called  the  Culex  fasciatus.  Giles's  description  of  the  ('///*./•  tiniads 
mosquito  agrees  more  closely  than  with  the  Culex  fasciatus.  He 
describes  the  difference  between  them.  He  is  inclined  to  consider 
them  a  genus  apart  because  they  lay  different  eggs. 

Dr.  C.  Finlay,  Habana,  expressed  his  admiration  for  the  work  of 
the  commission.  He  believes  that  this  session  of  the  con  II  go 

down  in  history  as  of   great  importance4  and   that    the  di 
between  his  opinion  and  that  held  by  ihe  commission  will  d 
in  the  course  of  time.     He  states  that  they  were  based  on  the  fact 
that  he  investigated   with  three  varieties  of  mosquitoes.   \\l.iie  the 
commission  has  been  restricted  to  one  variety;  that   the  b. 
placed  on  better  footing  for  obtaining  s  the 

negative  result  obtained  by  the  inocula'ion  of  mosqiiitoo.  of  short 
infection  should  not  induce  the  commission  or  the  board  to  make 
such  bard  and  biased  rules  as  are  evidenced  in  its  conclusion-. 

Dr.  Reed,  in  conclusion,  said  he  was  profoundly  impre><ed  with 
the  interest  and  attention  given  to  these  experiments.  In  rc'j-anl  to 

moral  aspect  of  the  Case,  he  did  not  think  that  an\  one  api  • 
the  position   in   which  he  found   himself     the  difficulties  (h 
his  path.     The  first  experiment   \\  as  made  on  a  memberof  the  board, 
Dr.  Carroll.     The  senior  member  expected  to  i.  bite  in  turn, 

but    was   nnexpertedly  called   north.      As  no  aniniid   could    \n>  ;/iven 
the  disease,  and  it  was  useless  to  follow  the  previous  indelinit 
ments,  it  was  absolutely   nrcr^iiry   to   make   tl  ••rimerr 

human  subjects,  or  otherwi  e  rolumea  «-nuld  have  been  and 


YELLOW   FEVEE.  89 

discussed,  and  yet  we  would  have  been  no  nearer  the  truth  than  at  first. 
No  progress  could  have  been  made  toward  an  exact  knowledge  of  the 
disease  unless  human  subjects  had  been  used.  All  experiments  were 
performed  on  persons  who  had  given  their  free  consent. 

In  reference  to  the  remarks  of  Dr.  Holbeck,  of  Charleston,  the  dis- 
infection of  vessels  should  by  no  means  be  dispensed  with,  but  only 
of  such  articles  as  bedding  and  clothing,  though  it  is  necessary  to  get 
rid  of  the  mosquitoes,  and  this  simplified  the  process  of  disinfection. 

In  regard  to  the  remarks  of  Dr.  Gutierrez,  in  reference  to  the  name 
of  the  mosquito,  Dr.  Howard,  of  Baltimore,  told  him  that  Culex 
fasciatus  is  identical  with  Culex  tiniads  as  described  by  Giles.  Theo- 
bolt  separates  Culex  tiniads  from  the  genus  Culex  and  places  it  in  a 
new  genus,  Stegamina.  These  lay  their  eggs  in  a  peculiar  way,  and 
there  is  also  a  difference  in  the  anterior  claws  of  the  male  insect  from 
those  of  the  other  Culex.  There  is  also  a  difference  in  the  larva  of 
the  Culex  fasciatus.  It  is  very  interesting  also  to  note  the  fact  that 
this  is  the  very  mosquito  that  Dr.  Finlay  used  in  his  experiments 
and  that  this  particular  mosquito  does  not  belong  to  the  genus  Culex; 
therefore  malaria  has  a  genus  of  its  own,  Anopheles,  and  yellow  fever 
the  genus  Stegamina. 


CM  MM  Kit'  4. 

THE  PROPAGATION  OF  YELLOW  FEVER— OBSERVATIONS  BASED 
ON  RECENT  RESEARCHES.' 

KB  REED.  M    I>  .  Surgeon,  Uniu-.i  ay, 

Mi:      1'Ki.Mi.r.M      LOT    <.I:MI.I:MKN     OF    THE     I- '  \<  i  i  n  :    If.     upon 
.;»t   of  your  kind  invitation  to  ho  present    with  you  to-night    my 
first  impulse  \\as  to  decline.    1    beg  that   you   will  not   attribute  this 
to  any  want  of  appreciation  on  my  part  of  the  honor  conferred,  hut 
solely  to  my  desire  to  avoid  what  1  felt  would  he  a  very  em h;. 
position    should    1    attempt   to   follow    in     the    footsteps    of    the    dis- 
tinguished  gentlemen    whom   you    have   invited    to    fill    this  position 
from  year  to  year.      Kecogni/ing  in   them,   as  all  willing  leader 
leaders  in   the   profession,    \\lio.    hy    their   well-con-idcied    addn 
have  been  able  to  add  so  much   to  the  scientific  interest   of  your 
annual  meetings,  I  could  hut  1W1  that  the  burden  which  you  | 
to  put  upon  me  was  greater  than  I  could  bear.     That.  nevcrtheli-s. 
I  am  here  in  the  capacity  of  your  annual  speaker  is  due  to  my  unwill- 
ingness even  to  appear  disobliging  to  this  old  ami  honorable  .• 
eiation  of  physicians,  among  whose  number  I  find   included 
of  my  most  valued  friends;  friends  who  in  years  gone  by  have  laboied 
so  faithfully  to  instill  into  my  mind  the  value  of  the  scientific  method. 
but  to  whom  I  have  been  able  to  make  such  small  ret  inn.     If,  there- 
fore, I  drew  some  encouragement  from  the  feeling  that  I  should  not 
be  wholly  among  strangers,  I  found  yet  more  in  the  thought   that 
such  an  eminent  body  of  physicians  as  this  faculty   must   ever  be 
willing  to  welcome  any  contribution   that  promises   to  shed    liirht 
upon  a  subject  hitherto  enshrouded  in  darkness,  and  which  tin- 
holds  out  the  prospect  of  an  addition  to  our  knowledge  in  the  I 
field  of  preventive  medicine. 

In  the  hope  that  what  I  have  to  say  to-night  may  contribute  to 
the  solution  of  a  somewhat  obscure  problem,  and  may  assist  u< 
hereafter  in  the  struggle  with  a  grave  epidemic  disease,  I  have  con- 
cluded to  present  for  you  i-  consideration  "The  propagati*  .-How 
fever,  based  on  recent  researches." 

Before  proceeding  to  the  discussion  of  this  subject,  it  is  fitting  that 
I  should  pay   brief  tribute  to  the  memory  of  a  former  member  of 
thiv  faculty.'  the  late   Dr.  Jesse  NV-    l-i/ear.   I'niled  States  Arm \        1 
can  hardly  trust  myself  to  speak  of  my  late  colleague,  since  the  men- 
tion of  his  name  brings  hack  Mich  scenes  of  anxiety   and  dcpre»ion 
as   one    ic, 'alls    only    with    pain.      Along    \\ilh    these   sad    mem. 
however,  come  Other  recollections  of  a  manly  and  fearless  devotion 
to  duty  sued  as   I   have  never  seen  equaled.     In  the  disci 
the  latter.  Dr.  Lazear  seemed  absolutely  tireless  and  quite  ol>li\ 

'  A-HP-SS  d  '.'•  on.-  hundn-d  !in.l  third  ami  I  "f  the  Medical  and  Chlrurgical  1 

Of  the  Stete  o(  Maryland.  . 

90 


YELLOW   FEVER.  91 

of  self.  Filled  with  an  earnest  enthusiasm  for  the  advancement  of 
his  profession  and  for  the  cause  of  science,  he  let  no  opportunity 
pass  unimproved.  Although  the  evening  might  find  him  discouraged 
over  the  difficult  problem  at  hand,  with  the  morning's  return  he 
again  took  up  the  task  full  of  eagerness  and  hope.  During  a  service 
of  less  than  one  year  in  Cuba  he  won  the  good  will  and  respect  of 
his  brother  officers  and  the  affection  of  his  immediate  associates. 
Almost  at  the  beginning  of  what  promised  to  be  a  life  full  of  usefulness 
and  good  works  he  was  suddenly  stricken,  and,  dying,  added  one 
more  name  to  that  imperishable  roll  of  honor  to  which  none  others 
belong  than  martyrs  to  the  cause  of  humanity. 

It  is  my  own  earnest  wish  that,  whatever  credit  may  be  hereafter 
given  to  the  work  of  the  American  commission  in  Cuba  during  the 
past  year,  the  name  of  my  late  colleague,  Dr.  Lazear,  may  be  always 
associated  therewith. 

I  do  not  propose  to  set  before  you  this  evening  so  much  the  views 
of  others  in  relation  to  the  etiology  of  yellow  fever,  or  to  the  conditions 
under  which  it  originates  and  spreads,  as  to  give  you  the  results  of 
my  own  experience  with  regard  to  the  manner  in  which  this  disease 
propagates  itself.  In  the  ordinary  course  of  Army  administration,  I 
found  myself  brought  in  contact  with  yellow  fever  during  the  sum- 
mer of  1900,  under  such  circumstances  as  permitted  me  to  give  my 
entire  time  to  the  study  of  its  etiology  and  propagation.  Permit  me 
here  to  remark  that  so  many  claims  have  been  made  as  to  the  specific 
cause  of  yellow  fever — claims  that  could  not  be  confirmed  by  other 
investigators — that  one  must  needs  feel  considerable  hesitancy  in 
considering  this  remarkable  disease  from  any  aspect.  I  must  con- 
fess that  I  have  experienced,  in  the  highest  degree,  this  feeling  of 
reluctance  to  write  or  speak  about  yellow  fever,  especially  when  I 
recall  the  frame  of  mind  of  myself  and  my  colleagues — that  of  utter 
perplexity  and  wonder — as  we  stood  by  the  bedside  of  patients,  or  at 
the  autopsy  table  of  those  who  had  died  of  this  mysterious  malady. 
I  trust,  therefore,  that  whatever  I  may  say  here  to-night  will  be 
considered  as  a  modest  expression  of  opinion  growing  out  of  an 
unprejudiced  study  of  yellow  fever,  for  the  most  part  from  the  point 
of  view  of  its  propagation. 

Although  considerable  attention  had  been  given  to  the  laboratory 
study  of  the  microorganisms  isolated  by  Sternberg  and  Sanarelli 
from  the  organs  of  yellow-fever  cadavers,  this  did  not  enable  one  to 
form  any  opinion  concerning  the  nature  of  the  disease  or  the  mode 
of  its  propagation. 

At  the  time  of  our  arrival  in  Cuba — June,  1900 — the  situation  as 
regards  the  etiology  of  yellow  fever  may  be  briefly  stated  as  follows : 
The  claims  of  all  investigators  for  the  discovery  of  the  specific  agent 
of  this  disease  had  been  disproved  by  the  exhaustive  work  of  Stern- 
berg/  published  in  1890,  except  that  made  by  Dr.  Sanarelli,  in  June, 
1897,  for  his  bacillus  icteroides.  I  need  not  take  up  time  here  with 
mention  of  those  who  had  investigated  Sanarelh's  claim,  except  to 
state  that  the  confirmation  of  his  discovery  came  chiefly  from  workers 
in  the  United  States,  of  whom  1  may  speak  of  Achinard  and  Woodson, 
of  New  Orleans,  and  especially  of  Wasdin  and  Geddings,  of .  the 

i  Keport  on  the  Etiology  and  Prevention  of  Yellow  Fever,  1890. 


92 

Marine-Hospital  8  .  in  a  report  '  submitted  duringthe 

v.l    in   the   full.  laim   for   the 

specific  «  their  confirmation  on 

tlit'  finding  of  this  bacillus  in  \  ellow  te\  er  studied 

by  them  in  the  .  ana.    Under  these  circumstance 

of  the  lir-t  Unportknce  that  we  should  give  our  entire  time  to  the 
Search  for  tocuftlt  *V/<  nmA  \  in  the  Indies  of  vellov, -fever  eases.  Tlu» 
result  of  this  stu  Jl  cases  during  life  and  1  1  auto] 

and    which  has    ah.  Q    in    our 

Preliminan  hist  meet  in-:  of  the  American  Public 

'0). 

Turning  for  a  moment  to  our  knowledge  concerning  the  mode  of 
of  yellow  fever,  t  he  sit  ua t  i<  .n .  \\  hen  .,:i  WOlfe,  was 

about  as  follows:  The  battle  for  or  air.  importation  ha\ 

already  deeided  in  favor  of  the  former  belief,  its  t  ran-;i!i--i(>iiity  from 
nlace  to  place  \vas  attributed  to  the  individual  ull'ectcd  by  tin 
but    especially    to    his    clothing;  With    the    proviso.    howcNer,    that 
intimately  connected  with  its  spread  was  involved  a  proper  constitu- 
tion of  the  atmosphere  of  the  place,  this  latter  due  ehielly  to  in-ani- 
tary  conditions  of  soil.     That   the  excreta  of  the  patient   contained 
the  specific  agent  of  the  disease  was  supported  by  many  g<»od  authori- 
ties.    That  the  disease  could  be  propagated  by  fomites  was  not  de- 
puted bv  anyone.     Against  its  spread  by  the  sick  and  by  fount  t 
quarantine  measures  were  being  then  directed. 

The  theory  of  Finlay  for  the  propagation  of  yellow  fever  by  the 
mosquito,  concerning  which  I  shall  presently  ha 
had  either  gained  no  credence  or  been  rejected  by  reason  of  the  ah-' 
of  any  results  that  had  been  presented  by  its  author  in  support  of  it. 
In   tfie  meantime,   and    before  we  had   completed   our    search    for 
Sanarelli's  bacillus,  certain  facts  had  been  cropping  out,  as  it   \ 
which  served  to  arrest  the  attention.     Just  here,  while  mentioning 
the  first  fact,  let  me  say  that  one  does  not  like  to  con)  ignorance 

of  such  a  well-known  disease  as  yellow  fever,  especially  bcl'«-i 
audience  some  of  whose  members  may  have  already  treated  cases 
during  the  last  epidemic  in  this  city,  in  the  year  1876;  and  yet  candor 
compels  me  to  record  my  very  great  surprise,  when  brought  fa< 
face  with  yellow  fever,  to  learn  that  attendance  on  patients  by  non- 
immune  nurses,  in  every  stage  of  the  malady,  involved  no  danger. 
In  other  word-,  that  yellow  fever,  both  in  the  wards  at  Columbia 
Barracks,  a-  well  as  in  the  wards  of  Las  Aninia-  Il<^pi;;i|.  Habana. 
was  not  contracted  by  the  attendants  under  circumstances  such  as 
those  in  which  typhoid  fever  and  Asiatic  cholera  are  too  often  c<m- 
•  •d.  Further  inquiry  along  this  line  seemed  to  indicate  that  the 
disease  had  not  been  contracted  in  hospitals,  even  during  the  earlier 
epidemic-,  when  disinfection  of  article-  of  clothing  and  bedding  was 

unknown. 

ud  fact  which  appeared  worthy  of  note,  uas  the  di-char 

pa tii m-  from  the  wards  ouring  early  convalescence,  and  their  i< 

to  the  companion-hip  of  their  comrades  \\ith  apparently   no  d; 
of  establishing  fresh  foci  of  the  disease.     This  hardly  seemed   in 
keeping  u  iih  the  pn  lie  agent  in  1 1  '  a  of  the  sick, 

third  fact  which  stood   «»ui    prominently  \\as  that,  in  certain  of 

our  cases,  no  growth  whatever  was  obtained  on  our  present  laboratory 

i  The  Cause  of  Yellow  Fever.    Washington.  19M. 

*  Tbt  Etiology  of  uinary  Note,    i'hll.  Med.  Journal,  Oct.  27, 1900. 


YELLOW    FEVER.  93 

media,  either  by  frequent  cultures  taken  from  the  blood  during  life 
or  from  the  organs  after  death.  In  other  words,  no  bacterium  was 
obtainable  by  aerobic  methods,  in  certain  of  our  cases,  either  during 
life  or  after  death.  This  result  had  considerable  weight  in  controlling 
our  future  work. 

During  the  time  that  these  cases  were  being  studied,  opportunity 
was  afforded  to  investigate  an  epidemic  of  fever 'which  was  prevailing 
in  Pinar  del  Rio  Barracks,  near  the  town  of  this  name,  distant  110 
miles  from  Habana,  and  of  which  fever  several  soldiers,  in  a  garrison 
of  about  900  men,  had  already  died.  A  visit  was  made  to  this  garrison 
with  my  colleague,  Dr.  Agramonte,  on  the  31st  day  of  July,  1900, 
and  a  body  sectioned  the  same  afternoon.  The  lesions  found  were 
those  of  yellow  fever.  Inquiry  showed  that  under  the  diagnosis  of 
"remittent  malarial  fever"  or  "pernicious  malarial  fever,"  the  disease 
had  been  prevailing  for  at  least  37  days  prior  to  our  arrival — July  21— 
and  that  about  35  cases  had  been  under  treatment  in  the  post  hospital, 
of  which  number  11  had  died.  As  the  true  nature  of  the  disease  had 
not  been  suspected,  no  precautionary  measures  had  been  taken  as 
regards  the  disinfection  of  bedding  and  clothing  used  by  the  patients, 
except  that  in  case  of  death  the  sheets  and  pillow  slips  were  put  in 
bichloride  solution  and  the  mattresses  and  pillow  exposed  to  sun- 
light. An  order  required  that  the  excreta  of  all  patients  under  treat- 
ment in  this  hospital  should  be  carefully  disinfected,  and  this  was 
probably  carried  out  fairly  well.  The  excreta  for  the  garrison  at  large 
were  incinerated  in  permanent  crematories,  fires  being  lighted  in 
these  twice  a  week. 

Notwithstanding  the  omission  to  disinfect  the  bulk  of  the  contami- 
nated articles  of  bedding  and  clothing,  the  disease  had  not  been 
contracted  by  the  nurses,  nor  by  the  other  patients  in  the  several 
wards,  nor  by  the  three  men  who  washed  all  of  these  articles.  A 
little  inquiry  showed  that  contaminated  clothing  was  in  all  of  the 
eight  barrack  rooms  without  apparent  detriment  to  the  occupants. 
Further  investigation  showed  that  a  death  from  yellow  fever  had 
occurred  in  this  garrison  as  early  as  May  16,  1900,  and  that  the  source 
of  infection  for  this  case,  as  well  as  for  the  present  outbreak,  was  in  the 
immediately  adjacent  town  of  Pihar  del  Rio,  to  which  fhe  soldiers 
had  free  access. 

An  interesting  observation  was  the  sudden  attack  of  yellow  feverT ' 
experienced  on  July  12,  1900,  by  a  general  prisoner  who  had  been) 
confined  in  a  cell  in  the  guardhouse  since  June  6,  1900.     His  death) 
occurred  at  the  post  hospital  on  July  18,  1900.     This  cell  was  occupied! 
at  the  time  by  eight  other  prisoners,  none  of  whom  contracted  the! 
disease,  although  one  of  them  continued  to  occupy  the  bunk  vacated ; 
by  the  sick  man.     As  these  nine  prisoners  had  been  kept  under  strict 
military  guard,  it  was  impossible  that  the  individual  attacked  could 
have  acquired  his  infection  in  the  town  of  Pinar  del  Rio.     He  was,  as 
far  as  could  be  ascertained,  exposed  to  no  source  of  infection  to  which 
his  companions  had  not  been  equally  exposed,  and  yet  he  alone 
acquired  the  disease.     It  was  conjectured  at  the  time  that  perhaps 
some  insect  capable  of  conveying  the  infection,  such  as  the  mosquito, 
had  entered  through  the  cell  window,  bitten  this  particular  prisoner, 
and  then  passed  out.     This  was,  however,  only  a  supposition. 

Two  instances  of  undoubted  exposure  to  fomites,  involving  four 
individuals,  came  under  my  observation  during  this  inspection.  In 


94 

the  one  case  a  box  of  dot  him:.  helon  n  soldier  who  had  died  of 

yellow  fever  on  July  3,  and  which,  had  been  packed  by  an  enlisted 
man  on  July  4,  and  placed  in  the  company  storeroom,  was  un- 
packed for  tile  purpose  of  making  an  inxentory  of  the  articles,  and 
carefully  repacked  on  duly  Is  !»y  t  \\ « •  noniinmune  soldier*,  who  did 
not  contract  the  disease  'by  this  exposure.  In  the  other  case  the 
very  bed  vacated  on  July  is  bv  the  commissary  sergeant,  who  w*a 
taken  sick  on  July  17,  and  died  on  July  ill.  upied  I 

noniinmune    soldier   on    the    nights  of    the    I'.Mh    and    LMMh  of  Julv. 
Although  this  individual  xvas  badly  frightened  when  the  true  character 
of  the  sergeant's  attack  \\a>  announced,  the  combination  of  fright 
and  exposure  to  fomites  was  not  sufficient  to  produce  an  atta. 
yellow  fever. 

The  data  gathered,  therefore,  during  the  inve>t  iiration  of  this  small 
epidemic  at  I'inar  del  Kio  did  not  tend  to  strengthen  one's  belief  in 
the  theory  of  the  propagation  of  yellow  fever  by  fomih •-.  Tin's  belief 
had  already  been  shaken  by  the  manner  in  which  the  di>ea-e  had 
spread  in  the  town  of  Quemados,  Cuba,  from  which  we  had  obtained 
cases  for  bacteriologic  study;  for  here  we  saw  the  disease  pa-s  fn»m 
No.  in-j  Real  Street  around  the  corner  to  No.  20  General  L 
and  thence  to  a  house  immediately  across  this  latter  street,  without 
the  passage  of  any  persons  between  these  three*  houses,  and  to  the 
exclusion  of  any  article  of  clothing,  as  the  three  families  had  no 
acquaintance  whatever  with  each  other.  Here  the  infection  was 
just  as  plainly  carried  through  the  air  as  it  had  been  taken,  through 
this  medium,  to  the  prisoner  in  the  cell  at  Pinar  del  Ki...  \\V 
observed  in  this  town  that  the  contagion  passed  down  (leneral 
Street  with  a  bound  to  the  distance  of  a  square,  passing  in  its  journey 
a  house  containing  two  nonimmunes,  only  to  return  a  few  days  later 
to  this  very  house  and  seize  upon  both  of  its  noniinmune  inn> 
This  hardly  seemed  in  keeping  with  the  idea  of  a  diffusible  p<»i-«»n 
carried  by  the  atmosphere.  During  our  first  week  on  the  island, 
we  noted  in  a  house  in  Quemados,  where  the  husband  and  wife  \\ere 
taken  down  with  yellow  fever  a  few  davs  apart,  that  neither  the 
young  daughter,  who  was  removed  to  a  place  of  safety  on  the  fourth 
day,  nor  an  attendant  who  had  remained  in  the  sick  room  for  the 
entire  24  hours  of  the  seventh  day,  had  acquired  the  di-ea-e:  but 
that  of  the  two  remaining  nurses  who  continued  to  perform  their 
duties,  one  was  seized  on  the  fourteenth  day  and  the  other  on  the 
fifteenth  day  with  an  attack  of  yellow  fever.  This  observation  was 
reenrded  at  the  time  for  what  it  was  worth.  Later  it  was  found  to 
harmonize  with  the  observations  which  had  been  made  by  Surg. 
Henry  K.  ( 'arter,  of  the  Marine-Hospital  Serviee.  in  Vs  I  shall 

rec i ir  to'these  observations  later  in  my  remarks,  it  will  suilice  to  here 
state  that  at  this  stape  of  our  investigation  it  seemed  to  me,  and  I 
so  expressed  the  opinion  to  my  colleagues,  that  the  time  had  armed 
when  the  plan  of  our  work  should  be  radically  changed;  that  the 
search  for  the  specific  agent  of  yellow  fever,  while  not  abandoned, 
should  be  given  secondary  ron-ideration.  until  we  had  first  definitely 
ted  something  about  the  way  or  wax  s  in  \\hi<  h  the  disease  \\as 
propagated  from  the  sick  to  the,  well.  I  felt  well-nigh  convinced 
that  we  could  obtain  no  light  whatever  upon  the  task  that,  had  been 
set  before  us,  unless  we  substituted  this  line  of  work  for  the  one  we 
had  been  pursuing,  and  that  in  view  of  the  ^plendid  work  of  Ross, 


YELLOW   FEVER.  95 

Bignami,  and  others  with  regard  to  the  propagation  of  malarial  fever, 
together  with  the  well-known  thermal  influences  intimately  con- 
nected not  only  with  the  epidemiology  of  the  disease  in  the  United 
States,  but  also  with  its  endemiology  on  the  Island  of  Cuba,  it  was 
of  the  highest  importance  that  the  agency  of  an  intermediate  host, 
such  as  the  mosquito,  should  either  be  proven  or  disproven. 

Remember,  if  you  please,  that  here  we^er^jle.ajing^witli..an  epi- 
demic disease  concerning  which  there  was  no  evidence  whatever  to 
show  that  it  had  ever  been  spread  by  contamination  of  either  water 
or  food;  that  it  had  always  demanded  a  certain  elevated  tempera- 
ture before  it  would  begin  its  progress,  which  latter,  both  in  its  man- 
ner and  rate,  was  quite  unlike  that  of  other  epidemic  diseases,  such 
as  smallpox  or  typhoid  fever  or  Asiatic  cholera;  that  once  having; 
begun  its  march,  110  hygienic  measures  ever  instituted  had  been  able 
to  arrest  its  course,  except  depopulation  of  the  locality  affected; 
that  while,  if  introduced  into  certain  localities,  it  would  readily  propa- 
gate itself,  those  sick  with  this  disease  could  be  carried  in  large  num- 
bers into  other  places  without  any  danger  of  its  spread — a  fact  which 
had  been  attested  in  hundreds  of  instances;  that  ships  with  nonim- 
mune  crews  could  remain  at  anchor  with  perfect  safety  at  about  300 
yards  from  an  infected  shore.  Couple  with  this  the  natural  law  by 
which  it  was  governed,  viz,  its  prompt  control  by  frost,  and  tell  me 
what  other  epidemic  disease  could  be  associated  in  the  mind  with 
this  except  malarial  fever. 

The  theory  that  the  spread  of  yellow  fever  could  not  b'e  explained 
by  the  assumption  of  a  diffusible  miasm  in  the  atmosphere,  but 
required  the  presence  of  an  intermediate  host,  appears  to  have  been 
first  advanced  by  Bj^jIjCI'Nott,  °^  Mobile,  Ala.,  in  March,  1848. 
His  views  were  givSTirTKIirin  the  New  Orleans  Medical  Journal  for 
that  year.  It  was  also  in  this  paper  that  Nott  suggested  the  mos- 
quito as  the  possible  agent  in  the  dissemination  of  malarial  fevers. 
He  evidently  did  not  have  in  mind  the  mosquito  as  the  bearer  of  the 
yellow-fever  poison,  but  rather  that  this  important  office  was  per- 
formed by  some  insect  or  insects  that  remained  very  close  to  the 
ground.  Referring  to  the  fact  to  which  all  writers  were  agreed,  that 
a  very  imperfect  barrier,  such  as  a  row  of  houses  or  of  trees,  would 
often  protect  dwellings  from  the  access  of  malarial  poison,  he  says: 

I  have  been  able  in  my  researches  to  discover  no  facts  of  this  kind  in  connection 
with  yellow  fever,  and  my  personal  observation  repudiates  this  in  toto.  We  never 
find  yellow  fever,  as  the  sportsman  says,  "up  a  tree,"  but  on  the  contrary  the  materies 
morbi,  whatever  it  may  be,  creeps  along  the  ground,  regardless  of  winds,  passing 
under  and  through  houses  and  trees,  etc.,  and  knowing  no  impediment  but  a  sheet 
of  water. 

Again : 

It  is  a  curious  fact  that  from  1829  to  1837  there  was  no  epidemic  of  yellow  fever  in 
Mobile,  and  during  this  time  the  streets  were  beautifully  shelled;  since  1837  we  have 
had  it  five  times  and  the  shelling  was  not  continued.  If  the  insect  theory  be  correct, 
could  the  lime  be  an  impediment  to  their  progress  across  the  street? 

To  Dr.  Carlos  J.  Finlay,  of  Habana,  must  be  given,  however,  full 
credit  for  the  theory  of  the  propagation  of  yellow  fever  by  means  of 
the  mosquito,  which  he  proposed  in  a  paper  read  before  the  Royal 
Academy  in  that  city  at  its  session  on  the  14th  day  of  August,  1881. 
From  that  date  to  the  present  time  Finlay  has  made  a  number  of 
valuable  contributions  to  the  origin  and  mode  of  transmission  and 


96  VER. 

prevention   of  ycllo.  l>urini:   this  time  his   \iews 

undergone  some  slighl  modification.     Startin;:  uith  the  idea  that  the 
tic   poison  adhered   to   the   mosquito's  proboscis  and   was  thus 
mechanically  transferred  to  the  individual  next  bitten  i  \\hich  specific 
.dined  by  him  in  lss7.  and  even  at  tl  «  ;  time,  to  he 

his  micrococcus  betragenUfi  febris  ilava".  he  later  IV.i  modified 
his  original  theon.  based  iinon  the  studies  of  'riieoh:dd  Smith  on 
Texas  lever,  "so  as  to  include  the  important  eireun.  the 

faculty    of   tran-minini:   the  yellow-  'in    need    not    he   limited 

to  the  parent  insert .  directly  contaminated  I  yellow-1 

patient  (or  perhaps  by  contact  with  or  feeding  from  hi-  cii-cha< 
hut   may  he  likewise  inherited   hy  the  n«  ration  of  1110-0,11 

•  '(1  from  the  contaminated   parent"    <\e\\    York   Medical 
May    J7.    HMMi'.      Of   the    KM)    individual-   experimented    upon    from 
June,   1881,   t"    May,    1895,   Finlay  claimed    to   have   produced    three 
cases  of  "mild   alDiiminuric  fever"    after   a    period   of    incubation 

.  ini:  fn>"i  5  to  L'")  day-:  hut  aa  he  exeivixed  no  eonirol  OVOT  tlie<e 
indUaduals,  to  the  exclusion  of  other  sources  of  infection,  no  \ 
could  be  attached  to  his  results.  If.  indeed,  one  \\ere  L'uided  by  the 
re-ults  obtained,  the  only  logical  eoin-ln-ioii  to  he  drawn  \\a-  that 
Kinlay  had  disproved  his  own  theory.  His  failure  to  produce  po-i- 
tive  result-  wliich  we  now  believe  to  be  due  to  the  fact  that  he  did 
not  keep  his  insects  for  a  sufficient  length  of  time  .inanimation 

before  applying  them  to  the  individual  to  be  infected  doiihile--  led 
Finlay  to  promulgate  the  later  idea  that  the4  bite  of  the  cnntamn 
mosquito,  while  not  producing  the  disease,  conferred  immunity  upon 
the  individual  bitten.  He  has  made  use  of  the  bite  of  the  contami- 
nated moscjuito  for  this  purpose  in  a  considerable  number  of  indi- 
viduals. Notwithstanding  tne  fact  that  Finlay  had  no  result-  to 
show  in  support  of  his  theory,  and  that  the  latter  had  been  wholly 
rejected  by  other  investigators,  the  argument  in  favor  of  an  inter- 
mediate host  seemed  so  strong,  as  I  have  already  stated,  that  I'u: 
investigation  along  this  line  was  determined  upon.  The  mosquito 
-elected  was  the  one  that  had  been  used  by  Finlay  in  hi-  previous 
work,  and  which,  with  Culex  pungens,  is  the  most  prevalent  and 
annoying  mosquito  in  the  city  of  Habana,  and  for  that  matter  in  all 
the  larger  towns  on  the  island.  Originally  designated  by  Fabr'n-ius 
as  Culex  fasdatus*  it  had  later  been  called  by  Hesvoid 
mosquito.  Unlike  Culex  jnnif/dis  this  mosquito  bites  by  day  u  uell 
as  during  the  nighttime.  Judging  from  m\  own  expeii.  ..uld 

say  that  its  favorite  1  lours  for  feeding  were  from  -1  p.  m.  to  in  p.  m. 

In  pur  preliminary"  note,  above  referred  to,  we  recorded.  amon-_r  1  1 
individuals  bitten  py  contaminated  mosquitoes  of  thi-  m 
negative  and  2  positive  result-;  the  attack  in  both  of  the  latter 
occurring  within  the  period  of  incubation  of  yellov  the 

circumstances  surroumling  the  infection  of  one  of  these  cases  was 
Midi  as  to  exclude  any  other  BOUTCe  of  infect  ion.  v.e  announced  the 
conclusion  that  ''the  nio-<juito  served  a-  the  intermediate  host  for 
t  he  parasite  of  yellow  fever.       Subsequent  observations  have  poi 
in  the  most  convincing  manner,  to  the  -Mimdne-s  of  this  conch; 
It    is  to  these  later  observation-  that    I    now  de-ire  to  invite  your 
attention. 

Interesting  ami  Important  to  otwrvc  that  sln.-««t  ho  publicationof<- 

•    •    •  •  .      fi  .  i,'.,  •     :  •  •    •      .  •        Col         •..;:"!'•;.  Bd*  p-nu:,  - 


YELLOW   FEVEK.  97 

Dismiss  from  your  minds,  if  you  please,  the  idea  that -yellow  fever 
is  so  prevalent  on  the  island  of  Cuba,  and  that  the  ways  of  acquiring 
the  disease  are  so  numerous,  that  experimental  results  obtained  at 
any  point  in  the  so-called  endemic  zone  of  yellow  fever  must  be 
thereby  vitiated.  Nothing  to  my  mind  could  be  more  improbable 
than  such  an  opinion;  for,  as  a  matter  of  fact,  yellow  fever  has  been 
confined,  during  the  year  1900,  to  Habana  and  a  few  other  towns, 
coast  or  inland,  and  has  not  been  present  elsewhere  on  the  island. 
Hence  any  location  selected,  provided  it  should  be  1  mile  from  such 
a  center  of  infection  and  surrounded  by  proper  safeguards,  would  be 
just  as  free  from  the  occurrence  of  yellow  fever  as  if  it  were  located 
10  miles  from  such  a  town.  My  own  experience  on  the  island  of 
Cuba  had  already  taught  me  that  yellow  fever  could  be  easily  kept 
out  of  a  military  garrison,  although  prevailing  in  epidemic  form  in  a 
town  less  than  1  mile  distant.  For  this  reason  it  was  not  considered 
advisable  to  establish  our  experimental  sanitary  station  at  a  greater 
distance  than  1  mile  from  Quemados,  Cuba.  Thus  Camp  Lazear 
could  be  easily  reached  by  the  members  of  the  board  and  was  con- 
veniently located  as  regards  its  base  of  supplies.  The  occurrences  at 
this  camp  fully  justified  this  decision.  Placed  in  an  open  field, 
which  was  fairly  swept  at  all  times  by  the  prevalent  winds,  and  having 
a  military  garrison  each  of  whose  members  had  been  personally 
selected  by  reason  of  former  good  conduct  and  interest  in  the  work 
to  be  here  undertaken,  no  difficulty  whatever  was  experienced  in 
maintaining  the  strictest  quarantine  against  the  outside. 

Let  us  now  present  to  you,  as  succinctly  as  possible,  our  observa- 
tions at  this  camp,  prefacing  what  I  shall  have  to  say  with  the 
remark  that  here  we  proposed  to  attempt  the  infection  of  nonimmune 
individuals  in  three  ways,  viz,  first,  by  the  bites  of  mosquitoes  that 
had  previously  bitten  cases  of  yellow  fever;  secondly,  by  the  injec- 
tion of  blood  taken  during  the  early  stages  from  the  general  circula- 
tion of  those  suffering  with  the  disease;  and,  thirdly,  by  exposure  to 
the  most  intimate  contact  with  fo mites.  For  this  purpose,  in  addition 
to  the  seven  tents  provided  for  the  quartering  of  the  detachment, 
two  frame  buildings,  each  14  by  20  feet  in  size,  were  constructed. 
These  buildings,  having  a  cubic  capacity  of  2,800  feet,  were  exactly 
similar,  except  that  one  of  them,  known  as  the  "Infected  mosquito 
building,"  was  divided  near  its  middle  by  a  permanent  wire-screen 
partition  and  had  good  ventilation;  while  the  other,  designated  as 
the  "Infected  clothing  building,"  was  purposely  so  constructed  as 
to  exclude  anything  like  efficient  ventilation.  These  houses  were 
placed  on  opposite  sides  of  a  small  valley,  about  80  yards  apart,  and 
each  75  yards  distant  from  the  camp  proper.  Both  houses  were 
provided  with  wire-screen  windows  and  double  wire-screen  doors,  so 
that  mosquitoes  could  be  kept  without  or  within  the  buildings,  as 
the  experimenter  might  desire. 

At  first  the  results  obtained  at  this  station  were  not  encouraging. 
From  November  20,  1900,  the  date  of  the  establishment  of  the  sta- 
tion, until  December  4 — a  period  of  2  weeks — we  had  tried  to  infect 
4  individuals,  with  entirely  negative  results.  Two  of  these  had  been 
bitten  twice,  at  intervals  of  3  days,  by  contaminated  mosquitoes 
which  had  been  kept  from  10  to  14  days  after  they  had  fed  on  yellow- 
fever  cases ;  while  the  other  2  nonimmunes  had  been  thrice  bitten,  at 
79965°— S.  Doc.  822,  61-3 :7 


98  YELLOW   PEVEK. 

the  same  intervals,  by  mosquitoes  that  had  bitten  cases  *>f  yellow 

:•  ID  !.>  1  s  da\  s  before.  As  the  weather  (luriiiLT  this  time  \\  M 
and  the  inserts  had  been  kept  at  room  temperature  (and  this  is  prac- 
Hy  outdoor  temperature  in  Cuba),  we  conjectured  that  the  nega- 
tive re-idt-  illicit.  perhaps,  be  thus  explained.  \Ye  remembered  that 
Daniels1  in  repeating,  durini:  the  winter  season,  Ross's  oh-ervations 
\\  ith  proteosonia  infection  of  birds,  had  obtained  a  much  smaller  per- 
centage of  successes  than  had  Ross,  who  \\<>rked  during  summer 
i  her.  We  would  have  been  glad  to  draw  some  encouragement 
from  our  negative  experiments,  also,  \\ith  infected  bedding.  l»ut.  M 
at  this  date  (Dec.  4)  our  3  subjects  had  been  sleeping  uith  fomite- 
only  4  nights  (which  is  within  the  period  of  incubation  of  the  di- 
ttos comfort  was  debarred. 

On  the  fifteenth  day  of  our  encampment    therefore  (Dec. 
p.  in.)  W(  ntrated  our  insects,  so  to -speak,  on  one  of  these  non- 

immunes — Kissinger  by  name — selecting  5  of   our   m«^t   promi-ini: 
mosquitoes  for  the  purpose.     These  haa  been  contaminated  as  f.-l 
follows:  Two,  15  days;  1,  19  days;  and  2,  21  days  pn-viou-ly.     This 
inoculation  was  more  successful, for,  at  the  expiration  of  .'-5  day 
9J  hours  the  subject,  who  had  been  under  strict  (quarantine  during 
1 5  days,  was  suddenly  sei/ed  with  a  chill  about  midnight .  I  >e<  emberS, 
which  was  the  beginning  of  a  well-marked  attack  of  yellow  fever. 

I  can  not  let  this  opportunity  pass  without  cixpre--in^  my  admi- 
ration of  the  conduct  of  this  young  Ohio  soldier,  who  volunteered  for 
this  experiment,  as  he  expressed  it,  "  solely  in  the  interest  of  humanity 
and  the  cause  of  science,"  and  with  the  only  proviso  that  he  should 
receive  no  pecuniary  reward.  In  my  opinion  this  exhibition  of 
moral  courage  has  never  been  surpassed  in  the  annals  of  the  Army  of 
the  United  States. 

The  following    morning    (Sunday,  Dec.   9,  at    10.30   a.   m.) 
selected  from  those  insects  that  had  bitten  Case  I,  one  mosquito  that 
seemed  to  us  to  possess  the  best  record  of  contamination,  as  it  had 
bitten  a  fatal  case  of  yellow  fever,  on  the  second  day  of  the  di 
19  days  before.     This  insect  was  applied  to  a  Spanish  immigrant, 
who  had  been  strictly  quarantined  at  our  station  for  19  days.     At  t  he 
expiration  of  3  days  and  11  hours  (Dec.  9,  9.30  p.  m.)  this  individual 
was  also  seized  with  an  attack  of  yellow  fever. 

In  the  meanwhile,  on  December  8,  1900,  at  4  o'clock  p.  m.,  we  had 

applied  to  a  young  Spaniard  three  of  the  mosquitoes  that  had,  three 

(lays  previously,  bitten  Case  I,  together  with  an  additional  mosquito 

contaminated  17  days  before.     At  the  end  of  4  days  and  L'O  hours 

(Dec.  13,  noon)  this  "Spaniard  suddenly  lost  his  vivacity  and  took  to 

his  bed.     The  following  morning  at    !>  a.   in.   his  febrile  paroxysm 

began.     His  case,  which  was  the  mildest  of  our  series,  was  also  ma  iked 

•  long  period  of  incubation,  vix.  :>  days  and  17  hours.     He  had 

i  in  quarantine  9  days. 

Decemoer  11,  at  4.30  p.  m.,  the  identical  -1  insects  which  had  bitten 
Caselll  were  fed  on  a  Spanish  immigrant  who  had  been  in  quarantine 
the  past  21  days.     At  the  expiration  of  3  days  and   1!»4  houi> 
(Dec.  15,  noon)  he  was  likewise  seized  with  yellow  fever. 

Thus  within  the  period  of  one  \\cek  December  '.'  to  IT,  uc  had 
succeeded  in  producing  an  attack  of  yellow  fever  in  i-m-h  of  the  l 

> On  trmiumiMion  of  Proteofom*  to  Bird*  by  the  Mosquito- Royal  Society,  Reports  of  Malarial  c-.n,- 
mlttM.    London,  WOO. 


YELLOW   FEVER.  99 

individuals  whom  we  had  caused  contaminated  insects  to  bite,  and 
in  all  save  1  of  the  5  nonimmunes  whom  we  had  originally  selected 
for  experimentation. 

It  can  readily  be  imagined  that  the  concurrence  of  4  cases  of  yellow 
fever  hi  our  small  command  of  12  nonimmunes  within  the  space  of 
1  week,  while  giving  rise  to  feelings  of  exultation  in  the  hearts  of  the 
experimenters,  in  view  of  the  vast  importance  attaching  to  these  re- 
sults, might  inspire  quite  other  sentiments  in  the  bosoms  of  those 
who  had  previously  consented  to  submit  themselves  to  the  mos- 
quito's bite.  In  fact,  several  of  our  good-natured  Spanish  friends 
who  had  jokingly  compared  our  mosquitoes  to  "the  little  flies  that 
buzzed  harmlessly  about  their  tables/'  suddenly  appeared  to  lose  all 
interest  in  the  progress  of  science,  and,  forgetting  for  the  moment 
even  their  own  personal  aggrandizement,  incontinently  severed  their 
connection  with  Camp  Lazear.  Personally,  while  lamenting  to  some 
extent  their  departure,  I  could  not  but  feel  that  in  placing  them- 
selves beyond  our  control  they  were  exercising  the  soundest  judgment. 
In  striking  contrast  to  the  want  of  confidence  shown  by  these  Anda- 
lusians  who  had  agreed  to  be  bitten  by  mosquitoes  was  the  conduct 
now  displayed  by  the  three  young  Americans,  who  had  consented  to 
jeopardize  their  lives  by  exposure  to  fomites  and  who,  as  a  matter  of 
fact,  had  already  spent  15  nights  in  a  small,  illy  ventilated  building, 
breathing  in  an  atmosphere  dreadfully  contaminated  by  the  soiled 
garments  of  yellow-fever  patients.  With  the  occurrence  of  these 
cases  of  mosquito  infection,  the  countenances  of  these  men,  which  had 
before  borne  the  serious  aspect  of  those  who  were  bravely  facing  an 
unseen  foe,  suddenly  took  on  the  glad  expression  of  "schoolbovs  let 
out  for  a  holiday,"  and  from  this  time  their  contempt  for  "fomites" 
could  not  find  sufficient  expression.  Thus  illustrating  once  more, 
gentlemen,  the  old  adage  that  familiarity,  even  with  fomites,  may 
breed  contempt. 

As  the  continued  good  health  of  those  who  were  occupying  the 
" infected  clothing  building"  pointed  strongly  to  the  harmlessness 
of  fomites,  the  next  experiment  at  this  station  was  undertaken  for  the 
purpose  of  demonstrating  that  the  essential  factor  in  the  infection  of 
a  building  with  yellow  fever  is  the  presence  therein  of  mosquitoes  that 
have  bitten  cases  of  yellow  fever. 

Accordingly  at  11.55  a.  m.,  December  21,  1900,  15  mosquitoes  were 
freed  in  the  larger  room  of  the  " infected  mosquito  building,"  which, 
as  I  have  said,  was  divided  into  two  compartments  by  a  wire-screen 
partition.  The  interval  that  had  elapsed  since  the  contamination 
of  these  insects  was  as  follows:  One,  24  days;  three,  12  days;  four, 
8  days;  and  seven,  5  days.  The  only  articles  of  furniture  in  this 
building  consisted  of  three  beds,  one  being  placed  in  the  mosquito 
room  and  two  beyond  the  wire  screen,  these  latter  intended  to  be 
occupied  by  two  " control"  nonirnmunes.  The  articles  of  bedding 
as  well  as  the  bedsteads  had  been  carefully  disinfected  with  steam. 
At  noon  on  the  same  day,  5  minutes  after  the  mosquitoes  had  been 
placed  therein,  a  plucky  Ohio  boy,  Moran  by  name,  clad  onlv  in  his 
nightshirt,  and  fresh  from  a  bath,  entered  the  room  containing  the 
mosquitoes,  where  he  lay  down  for  a  period  of  30  minutes.  On  trie 
opposite  of  the  screen  were  the  two  controls"  and  one  other  non- 
immune.  Within  2  minutes  from  Moran's  entrance  he  was  being 
bitten  about  the  face  and  hands  by  the  insects  that  had  promptly 


100  YELLOW    PEVML 

settled  down  upon  him.     Seven  in  all  hit  him  at  this  visit.     At  4.30 

:..  the  same  day,  he  again  rut.  .1   remained  '20  minute*. 

during  which  time  5othen  hit  him.  The  following  day  at  -I.:i0  p.  in.. 
he  again  entered  and  remained  1  .">  minutes,  durffiff  which  time  :> 
insects  bit  him.  making  the  nnmher  1  .">  that  had  fed  at  the-e  three 
visits.  The  building  \\as  tlien  d«-  cpt  that  the  two  non- 

imnn  MtroU"  continued  to  OOCUpJ  the  heds  on  tlie  noninfeeted 

Mde  of  the  screen.  On  Christmas  morning,  at  11  a.  m..  this  brave 
lad  \\as  Mricken  \\ith  yellow  fever,  and  bad  B  -harp  attack,  which 
he  hore  without  a  murmur.  Tlie  period  of  incubation  in  this 
case  was  3  days  and  '2:\  hour*,  counting  from  liis  1ir-t  \i-ii.  or  - 
days  and  17J*  hours  if  reckoned  from  his  la-t  viMt.  The  t\\o 

itrols''  who  liiid  slept  each  night   in  this  house,  only   protected 
hy   tlie  wire  l>ut    breathing  the  common  atraospnere  of  the 

building,  had  remained  in  good  health.      They  continued  to  BO  remain, 
although  required  to  sleep  here  for   1M  additional  nighN.      A^  M 
liad  remained  in  strict  quarantine  for  tlie  period  of  ::_'  days  prior  to 

ittack.   the  source  of  his  infection   must    he   found    \\ithin   this 
house. 

In  the  order  of  succession,  the  next  experiment  undertaken  at  this 
camp  was  the  injection  of  blood,  taken  from  Case  V  (Moran  .  heneath 
the  -kin  of  a  Spaniard,  hut  I  will  defer  further  mention  of  this  li: 
experimentation  until  I  have  completed  the  mos<piit<  bete 

are  by  far  the  most  important.      I,  therefore,  invit  iitention 

to  Case  VI,  Martinez  by  name.  His  case  is  of  inteiv-t  as  hearini: 
upon  the  number  of  days  which  must  elapse  after  the  contamination 
of  the  mosquito  before  it  can  convey  the  disease  to  a  second  indi- 
vidual. 

An  additional  point  of  some  importance,  I  think,  is  that  win 
prior  to  the  time  of  Moran' s  infection  (Case  V)  the  contamin. 
mosquitoes  had  been  taken  to  the  men  in  their  tents  and  there  applied. 
from  this  date — December  17 — the  subjects  were  invited  to  vi 
particular  room  attached  to  our  "Mosquito  building."    hut    quite 
^epaiate  from  it,  where  the  contaminated  insects  wei  •  i  um- 

mer  temperature,  and  were  there  given  the  opportunity  of  e\po>in_u; 
themselves  to  an  attack  of  yellow  fever  by  putting  their  hand-  in-ide 
of  certain  mosquito-inhabited  jars.  I  may  as  well  t"ll  you  now  that 
of  seven  persons  who  availed  themselves  of  this  privilege  five 
acquired  yellow  fever. 

After  a  quarantine  period,  therefore,  of  9  days.  Marline/  \i>ited 
this  room  on  December  17.  I'.IOO.  and  was  bitten  hy  ll  mo^|iiitoes 
which  4  days  before  had  fed  upon  Case  I  of  this  series.  The  result 

Was    quite    negative.       December   24,    or   on    the    eleventh    <lay    after 

•  out animation,  the  subject-  was  again  bitten  by  7  of  these  insects — 
all  that  remained  of  the  original  14.      Again  no  infection  took  place. 
Aft ei- r,  full  days,  or  on  December  :>().  at   11  a.  m..  Marline/ v 
bitten   by   the  surviving    1  of  these  mosquitoes,   i.   e..   on   the  st 
teenth  day  after  their  contaminat  ion.      On  the  fourth  day  thereafter, 
.lanuary  I,    1901,  at  10.30  a.  m.,  he  was  sei/ed   \\ith  yellow  f. 
which  ran  a  tynical  cour-e.     The  period  of  incubation  wa 
22i  hours.     Although  we  can  not  say  on  what  particular  day  tln^e 
insects  became  capable  of  conveying  the  disease,  we  are  able  to  st  ate 
that  they  were  incapable  of  Infecting  on  the  fourth  or  eleventh  day 


YELLOW    FEVER.  101 

after  contamination.  This  experiment  agrees  with  others  that  we 
have  made  during  this  investigation  and  in  which  we  have  failed  to 
convey  the  disease  by  the  bites  of  insects  at  intervals  varying  from 
2  to  9  days  after  contamination.  These  observations  seem  to  indi- 
cate that  after  the  parasite  has  been  taken  into  the  mosquito's  stom- 
ach a  certain  number  of  days  must  elapse  before  the  insect  is  capable 
of  reconveying  it  to  a  second  individual.  This  period  probably  rep- 
resents the  time  required  for  the  parasite  to  undergo  its  cycle  of  devel- 
opment and  reach  the  mosquito's  salivary  glands,  and,  as  far  as  our 
experience  goes,  would  appear  to  be  about  12  days  in  summer  weather 
and  most  probably  about  18  or  more  days  during  the  cooler  winter 
months.  Case  VI,  therefore,  does  not  support  the  opinion  of  Finlay 
that  the  bite  of  the  contaminated  mosquito  confers  immunity  against 
a  subsequent  attack  of  the  disease,  since  we  have  seen  that  neither 
the  bites  of  14  insects  on  the  fourth  day  nor  the  bites  of  7  on  the  elev- 
enth day  after  contamination  prevented  in  the  least  the  conveyance 
of  the  infection  by  the  bites  of  4  only  of  these  mosquitoes  on  the  seven- 
teenth day. 

I  will  now  ask  you  to  look  at  Case  IX,  as  this  case  serves  to  illus- 
trate some  points  of  interest.  In  the  first  place,  this  subject,  an 
American,  was  bitten  by  insects  that  had  fed  upon  Case  I  of  our  series 
on  the  third  day  of  his  illness ;  that  is,  during  the  secondary  fever  which 
followed  a  complete  intermission  in  this  case.  Secondly,  these  mos- 
quitoes had  been  kept  alive  on  sugar  and  water  for  a  period  of  39  days 
before  being  applied  to  Case  IX.  Of  the  original  5  insects  that  had 
bitten  Case  I  on  the  third  day,  4  were  still  alive  on  the  thirty-ninth  da}r 
thereafter  and  3  showed  every  evidence  of  good  appetite.  Thirdly, 
this  particular  subject  having  passed  21  nights  in  the  "Infected  cloth- 
ing building,"  during  which  time  he  was  exposed  to  the  most  intimate 
contact  with  fomites,  without  apparent  detriment  to  his  health,  had 
been  kept  in  strict  quarantine  for  yet  30  days  longer  at  Camp  Lazear. 
At  the  expiration  of  this  time,  or  on  January  19,  1901,  at  4.30  p.  m.,  he 
visited  our  mosquito  room,  where  he  was  bitten  by  these  39-day-old 
insects,  3  in  number.  This  inoculation  was  followed  by  an  attack  of 
yellow  fever  of  moderate  severity,  which  began  at  4  p.  m.,  January 
23,  the  period  of  incubation  being  3  days  23J  hours. 

Case  XII  you  will  find  of  equal  interest,  as  this  individual  was  in- 
fected, in  the  same  room,  by  the  bites  of  two  of  these  same  mosquitoes 
on  the  fifty-first  day  after  their  contamination,  the  period  of  incuba- 
tion being^  3  days  2^  hours  and  the  character  of  the  attack  mild, 
while  Case  XIII  will  conclusively  demonstrate  that  these  identical 
insects,  on  the  fifty-seventh  day  after  their  contamination,  were  not 
only  capable  of  conveying  the  infection,  but  of  producing  an  attack  of 
such  severity  that  the  subject's  life  hung  in  the  balance  for  several 
days.  I  regret  to  have  to  state  that  the  individual  who  had  con- 
sented to  be  bitten  by  these  insects  on  the  sixty-fifth  day  after  their 
contamination  failed  to  fulfill  his  promise  at  the  last  moment;  so 
that  otherwise  I  can  not  say  to  what  old  age  these  mosquitoes  might 
have  attained.  Deprived  of  further  opportunity  to  feed  on  human 
blood,  one  died  on  the  sixty-ninth  day  and  the  other  on  the  seventy- 
first  day  after  their  original  contamination.  The  duration  of  life  in 
the  case  of  these  mosquitoes  will  readily  explain  how  the  poison  of 
yellow  fever  can  remain  even  in  a  depopulated  area  for  a  period  of 


102  YELLOW  FEVER. 

2i  months;  so  that,  as  is  well  known,  those  who  enter  the  infected 
area,  even  at  the  expiration  <>f  this  period,  are  liable  to  acquire  the 
disease. 

\IY  i^  tliat  of  our  tenth  and  last  successful  moMjuito  inl'cc- 
tii»n  at  Camn  La/ear.  This  individual  after  j:>  davs'  (juarantine, 
having  been  bitten  on  1-Ybruarv  7.  1901,  at  1*  |>.  n:..  l>y  t  \\  o  moxjui- 
toes  on  the  sixteenth  day  after  their  contamination.  \\as-  seized  \\ith 
an  attack  of  \dlo\\  ferer  at  noon,  February  in,  after  an  incubation 
stage  of  2  days  22  hours. 

Thus  you  will  observe  that  at  this  station,  under  strict  <niarantine 
precautions,  we  succeeded  in  conveying  the  disease  to  in  nonimmuncs 
DV  means  of  the  bites  of  mosquitoes  tnat  ha<l  previously  fed 
of  yellov.  .1    interval  varying  from   Hi  to  57  days  befoic  being 

applied  to  the  person  to  be  infected:  that  the  attack  of  yellow  fever 
always  followed  the  bite  of  the  mosquito  within  the  period  of  inculm- 
tion  of  this  disease,  and  that  during  the  period  which  elapsed  from 
December  .">.  I'.ioO,  the  date  of  our  first  inoculation,  till  February  7, 
1901,  the  date  of  our  last  inoculation  «'..">  days),  the  order  of  occur- 
rence of  these  cases  corresponds  with  the  order  of  inoculation,  except 
that  Case  II,  having  a  longer  incubation  period  than  Case  III.  the 
order  of  their  relative  occurrence  became  reversed. 

Table  I  serves  to  illustrate  this  point. 

By  an  examination  of  this  table  it  will  be  seen  that  of  i:$  individuals 
whom  we  attempted  to  infect  by  bites  of  contaminated  moxp: 
we  succeeded  in  10,  or  76.92  per  cent.  Of  the  three  negative  cases,  it 
will  be  observed  that  one  (Case  VI),  who  had  reacted  nc^ativch  t<> 
the  subcutaneous  injection  of  1.5  c.  c.  of  blood  on  Dec-em  her  26,  1900, 
also  reacted  negatively  to  the  bites  of  mosquitoes  on  January  8,  1  !'<)  1 . 
and  this  notwithstanding  the  fact  that  he  was  bitten  by  tl  lame 

insects  which  nine  days  oefore  had  infected  Case  VII.     We  have  L 
ground  for  the  opinion,  therefore,  that  this  Spaniard  may  be  lo« 
upon  as  one  who  possessed  a  natural  immunity  to  yellow  fever,  ( 
cially  as  he  was  tne  only  one  of  five  persons  who  did  not  develop  the 
disease  after  receiving  an  injection  of  blood  taken  from  the  general 
circulation,  and  was  also  the  only  one  of  five  nonimmuncs  who  did 
not  contract  yellow  fever  when  bitten  by  insects  \\hich  already  had 
been  proven  capable  of  conveying  the  disease  to  other  im livid 

\ "III.  while  negative  to  mosquito  inoculation  on   December  Js 
and  _)(.».  ]'.»()(),  reacted  positively  to  a  blood  injection  on  Janu- 

ary   8,    1901.     This    particular    individual,    Jernigan.    entered    our 
"infected  mosquito  building''  on    December  _'s  ;iml   LMJ,    p.Min.   one 
week  after  Moran's  visit,  and   \\as   bitten  on  each  occasion   by  one 
mosquito.     As  66  per  cent  of  the  mosquitoes  freed  in  the  buildin 
December  21,  1900,  had  already  been  destroyed — m<»>t  pn.hahl 
the  small  red  ants  that  were  present  in  considerable  numbers     the 
subject  may  have  been  bitten  by  in-ects  that  were  not  more  than  i;; 
days  old,  in  which  ca-e  he  \\oiild  hardly  have  become  infected.     While 
considering  the  advisability  of  adding  other  contaminated  inse< 
those  in  the  house  for  the  purpose  of  infecting  .IernLran.  opp«»i -tunit  \ 
presented  for  making  a  blood  injection,  and,  as  he  was  the  only  avail- 
able subject  in  the  camp  at  the  time,  it  was  determined  to  mak> 
of  him  for  this  purp. 

c  XIII.  our  third   negative   eaefl  <>f  mosquito   inoculation,  was 
bitten  by  12  mosquitoes  that  had  fed  on  Case  Vll  within  s  hours  of 


YELLOW   FEVER.  103 

the  commencement  of  his  attack.  Although  these  insects  were  22 
days  old  when  applied  to  Case  XIII,  on  January  25,  1901,  no  result 
followed  the  bites.  As  the  subcutaneous  injection  of  2  c.  c.  of  blood 
taken  from  the  general  circulation  of  Case  VII,  at  the  end  of  24  hours, 
produced  an  attack  of  yellow  fever  in  Case  VIII  within  the  period  of 
incubation,  it  would  appear  to  indicate  that  the  mosquito  at  certain 
periods  of  the  disease  may  fail  to  obtain  the  parasite  owing  to  its 
absence,  at  that  particular  time,  from  the  capillary  circulation.  This 
is  not  unlike  what  we  sometimes  find  as  the  result  of  an  examination 
of  the  blood  of  malarial  fever,  especially  in  the  sestivo-autumnal  type 
of  the  disease.  Table  I  also  shows  that,  in  addition  to  the  positive 
case  (VIII)  to  which  I  have  already  invited  your  attention,  we 
obtained  three  other  positive  results  by  the  subcutaneous  injection 
of  blood  taken  from  the  general  circulation  on  the  first  and  second 
days  of  the  disease,  viz,  Cases  VIII,  XI,  XII.  The  quantity  of  blood 
injected  in  these  three  cases  was  1.5  c.  c.,  0.5  c.  c.,  and  1  c.  c.,  respec- 
tively. The  production  of  yellow  fever  in  this  way  is  of  much  scientific 
interest — first,  as  serving  to  confirm  what  the  mosquito  inoculations 
had  already  shown,  viz,  that  the  parasite  is  present  in  the  general  cir- 
culation; second,  that  passage  through  the  body  of  the  mosquito, 
although  this  would  seem  to  be  nature's  method,  is  not  absolutely 
essential  in  the  life  history  of  this  microorganism ;  and  third,  that  the 
period  of  incubation  of  the  disease,  when  thus  produced,  corresponds 
fairly  closely  to  that  occasioned  by  the  mosquito's  bite.  A  point  of 
considerable  importance  brought  out  by  the  blood  injection  was  the 
absence  from  this  blood,  on  careful  bacteriologic  culture,  of  any  bac- 
terium which  grows  on  our  ordinary  media  by  aerobic  methods,  thus 
excluding  absolutely  the  bacillus  icteroides  of  Sanarelli  from  further 
claim  as  the  specific  agent  of  yellow  fever. 


104 


YKLU>\V    FKVKK. 


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ft.   : 


fcfi      :      :»fc  : 


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ft 


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"»'»" »'=" a  a  *8  §y«°'ssi  a^  s  -'  -' 


g::a:g 


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>  *•' 


YELLOW   FEVER.  105 

You  will  recall  that  we  undertook  at  Camj>  Lazear  still  a  third 
method  of  propagating  this  disease,  viz,  by  fomites.  I  must  now  tell 
you  that  during  the  whole  time  that  we  were  producing  cases  of 
yellow  fever  by  the  bite  of  the  mosquito  and  by  blood  injection,  we 
were  leaving  no  stone  unturned  in  order  to  produce  the  disease  by 
contact  with  fomites.  Sleeping  every  night  in  the  "Infected  cloth- 
ing building/'  to  which  no  sunlight  ever  came,  and  in  which  the 
circulation  of  air  was  purposely  made  as  defective  as  possible;  en- 
gaged in  the  morning  in  packing  boxes  with  garments  much  soiled 
by  contact  with  the  bodies  and  excreta  of  yellow-fever  patients,  and 
at  night  unpacking  these  same  boxes  in  order  to  obtain  articles  for 
their  beds  and  clothing  for  their  bodies — in  other  words,  sleeping  in 
the  very  beds  and  garments  just  vacated  by  cases  of  yellow  fever, 
seven  nonimmune  young  Americans,  averaging  each  21  nights  amid 
such  uninviting  surroundings,  came  out  of  this  pesthouse,  so  to  speak, 
at  the  expiration  of  their  term  none  the  worse  for  their  experience. 
Not  one  had  contracted  the  disease. 

In  the  light  of  these  results  we  can  hardly  be  expected  hereafter  to 
lend  much  credence  to  such  observations  as  that  given  by  Harvey 
Brown,  in  1872, 1  as  narrated  by  Dr.  A.  A.  Baldwin,  of  Jacksonville, 
Fla.,  presumbly  from  memory,  some  13  years  after  the  event.  In 
this  instance  two  children  in  Jacksonville,  Fla.,  "contracted  the 
disease  by  being  present  at  the  opening  of  a  trunk  belonging  to  their 
uncle  who,  a  few  days  before  leaving  Habana,  had  visited  the  yellow- 
fever  hospital,  where  he  passed  by  the  beds  of  those  who  were  throw- 
ing up  black  vomit;  and  this,  notwithstanding  the  fact  that  his  coat, 
the  only  woolen  clothing  he  had  on  at  the  time,  had  been  sponged 
with  alcohol  after  his  return  from  the  hospital! " 

Or  this,  recorded  by  Rochester,2  as  an  example  "of  the  wonderful 
tenacity  with  which  fomites  hold  the  pestiferous  material"  and  after- 
wards "convey  it  to  mankind  with  intense  effect."  "In  September, 
1856,  an  infected  ship  from  Cuba  was  detained  at  the  quarantine 
anchorage  off  Staten  Island,  N.  Y.  Several  passengers  died,  and 
some  were  ill  on  board.  The  garments  and  bedding  were  thrown 
overboard.  Bay  Ridge,  a  delightful  suburban  neighborhood  of 
Brooklyn,  lies  directly  across  the  bay,  distant  about  1  mile  from  the 
anchorage  mentioned.  The  wind  and  tide  deposited  a  number  of 
garments  that  had  been  thrown  away  on  the  beach  which  terminated 
the  lawn  of  Col.  Charles  Prince,  an  old  and  respected  resident.  In 
taking  his  usual  morning  walk  he  discovered  the  clothing  and  ex- 
amined it  with  his  cane,  not  otherwise  handling  it.  He  had  no  sus- 
picion that  it  came  from  quarantine  and  never  saw  it  again.  In  four 
days  he  was  taken  illl  and  died  in  a  week  of  yellow  fever."  We  lose 
our  faith  in  this  brine-soaked  bedding  when  we  find,  according  to 
Elisha  Harris's  report,3  that  on  the  Long  Island  shore,  directly  oppo- 
site the  quarantine  grounds  (Bay  Ridge)  6  cases  of  yellow  fever  and  3 
deaths  from  black  vomit  had  already  occurred  between  the  13th  and 
21st  of  July,  1856,  and  that  "from  the  latter  date  the  malady  ex- 
tended fearfully  until  it  had  visited  nearly  every  dwelling  on  the 
shore  of  that  beautiful  Bay  Ridge,  30  cases  and  15  deaths  having 
occurred  in  that  district  previous  to  August  1." 

1  Report  on  Quarantine,  1872,  pp.  34  and  35. 

2  Transactions  Am.  Med.  Association,  vol.  30, 1899,  pp.  128, 129. 
*  Annual  Report  of  the  Physicians  of  Marine  Hospital,  1857. 


106  YELLOW   FEVER. 

I  could  quote  many  other  instances  contained  in  the  literature,  but 
as  not  one  of  them,  as  far  as  my  search  has  gone,  will  hear  the  slur': 
intelligent  critici-m.  I  \\ill  not*  further  trespass  on  your  time  ex  cept  to 
say  that,  in  my  opinion,  every  epidemic  of  yellow  fever  that  has  otc  uned 
in  the  United  States,  both  prior  to  and  since  tlie  period  when  disinfec- 
tants were  used,  has  pointed  in  the  plainest  manner  to  the  innoceii 
fomites  as  a  means  of  propagation  of  this  disease;  for  with  the  on 
cold  weather  and  under  those  conditions  of  lessened  ventilation  <»fd\u  11- 
ings  and  artificial  heat  that  should  have  aided  in  the  spread  of  the 
epidemic,  just  the  contrary  ell'ect  has  always  resulted,  t'nder  the  cir- 
cumstances one  must  eitner  conclude  that  an  external  temperature 
of  32°  F.  is  quite  sufficient  to  bring  about,  and  that  speedily,  the 
thorough  disinfection  of  the  many  tons  of  infected  clothing  and  bed- 
ding contained  in  the  houses  of  a  large  city  at  the  end  of  an  epidemic 
of  yellow  fever  or  that  fomites  have  no  part  in  the  incp.-i-  at  i«m  of  the 
disease.  The  latter  conclusion,  it  seems  to  me,  is  the  only  intelligible 
one,  in  view  of  our  present  knowledge  of  the  disinfectant  action  of 
oold  on  bacteria. 

Let  us  now  see  if  there  are  any  facts  observed  by  others  in  connec- 
tion with  the  ordinary  propagation  of  yellow  fever  \vhich  Mipport 
those  recorded  by  us  as  the  result  of  mosquito  bites  at  Camp  La/ear. 
Since  in  our  limited  experience,  affecting  'J:*  individual-,  we  have  not 
observed  the  production  of  the  disease  by  the  bite  of  the  nioxjnito 
within  less  than  12  days  after  contamination,  we  would  expect  that, 
when  a  case  of  yellow  fever  was  imported  into  a  town  or  house  where 
the  conditions  were  favorable  for  its  propagation,  a  secondary  case 
would  not  occur  within  a  less  period  of  time  than  about  14  or  more 
days.  I  may  say  that  various  observers  have  noted  that  alter  the 
occurrence  of  the  first  case  in  a  town,  a  considerable  interval  clap-e> 
(2  or  3  weeks)  prior  to  the  appearance  of  other  cases.  Although  such 
general  statements  are  of  value,  what  we  need  are  exact  observa- 
tions recorded  under  such  conditions  that  the  secondary  cases  can  be 
positively  referred  to  a  certain  limited  source  of  infection.  This,  of 
course,  can  best  be  done  where  the  disease  has  been  imported  into 
small  settlements  or  into  isolated  houses,  and  it  was  under  just  such 
favorable  circumstances  that  Carter,  of  the  Marine  Hospital  Service, 
made  his  observations  at  Orwood  and  Taylor,  Miss.,  in  1898,  "on  the 
interval  between  the  infecting  and  secondary  cases  of  yellow  lc  , 
Here,  in  a  community  of  more  than  average  intelligence,  con-i-tini: 
"not  of  a  town,  or  even  a  hamlet,  but  only  of  a  neighborhood,"  as 
Carter  puts  it,  it  was  possible  to  record  with  accuracy  the  date  of 
introduction  of  the  infecting  cases  and  the  date  of  occurrence  of 
secondary  cases. 

Table  II  gives  the  results  of  this  investigation. 

This  table  shows  that  of  16  houses  in  which  the  interval  between 
the  infecting  case  and  the  first  secondary  case  was  recorded,  l.r>.  or 
93.7  per  cent,  correspond  with  the,  mosquito  interval;  that  is,  the 
secondary  cases  occur  at  just  tho  interval — 13  to  23  days — when  we 
would  expect  them  to  develop,  provided  the  mosquito  was  concerned 
in  tho  propagation  of  the  disease.  It  will  he  observed  that  in  only  1 
of  the  16  first  secondary  cases  was  the  interval  as  short  as  11  days 
and  15  hours.  If  the  commencement  of  tho  attack  in  this  case  has 
been  recorded  correctly,  it  would  indicate  that  the  number  of  days 


YELLOW   FEVER. 


107 


which  we  have  given  as  "about  12"  for  the  development  of  the  para- 
site within  the  mosquito  would  have  to  be  shortened  somewhat — 
probably  to  10  days.  In  our  first  successful  experimental  case,  where 
the  disease  was  produced  by  the  bite  of  the  mosquito  on  the  twelfth 
day  after  the  insect's  contamination,  we  could  not  say,  of  course,  that 
this  particular  mosquito  would  not  have  conveyed  the  infection  had 
it  been  allowed  to  bite  on  the  tenth  or  eleventh  day  after  contamina- 
tion. 

On  the  other  hand,  if  we  take  all  the  secondary  cases  that  occurred 
in  these  16  houses,  we  will  find  that  of  a  total  of  71  cases,  only  1 
developed  the  disease  after  so  short  an  interval  as  11  days  and  15 
hours;  in  other  words,  70,  or  98.5  per  cent,  of  the  secondary  cases 
occurred  after  an  interval  of  13  days.  As  a  matter  of  fact  only  2  of 
these  secondary  cases  occurred  within  a  less  period  than  14  days,  1 
developing  on  the  twelfth  and  the  other  on  the  thirteenth  day. 

TABLE  II. — Interval  between  infecting  and  secondary  cases  of  yellow  fever. 


House. 

Year. 

Date  of 
infecting 
cases. 

Date  of 
first  sec- 
ondary 
case. 

Inter- 
val in 
days. 

Next  sec- 
ondary 
case. 

Number 
of  second- 
ary cases. 

Orwood.  Miss 

1 

1898 

Aug     6 

Aug   23 

164 

Aug    24 

6 

Do  

2 

1898 

Aug.  29 

Sept.  13 

15 

Sept.  13 

6 

Do 

3 

1898 

do 

Sept.  18 

20 

Sept   18 

4 

Do... 

5 

1898 

Aug.  31 

Sept.  29 

29 

Oct.     2 

3 

Do 

6 

1898 

do 

Sept  20 

204 

Sept.  20 

5 

Do... 

7 

1898 

Sept.    3 

Sept.  26 

23 

Sept.  30 

6 

Do 

8 

1898 

Sept.  17 

Oct.     8 

21 

Oct      8 

2 

Do.. 

9 

1898 

Aug.  31 

Sept.  22 

214 

Sept.  22 

4 

Do 

10 

1898 

Sept.    4 

Sept.  20 

16 

do 

2 

Do.. 

11 

1898 

Sept.  25 

Oct.     8 

13 

1 

Do 

15 

1898 

Sept.    2 

Sept.  22 

204 

1 

Do.. 

16 

1898 

Aug.  29 

Sept.    9 

U1J 

Taylor,  Miss 

1 

1898 

Aug.    7 

Aug.  27 

20 

Sept.    3 

13 

Do... 

2 

1898 

Aug.  17 

Sept.    2 

16 

Sept.    6 

8 

Do 

3 

1898 

Aug.  10 

Aug.  25 

15 

Aug    28 

2 

Edwards,  Miss  ...                            ... 

1897 

Aug.    8 

Aug.  22 

14 

Aug.  26 

10 

1 11  days  15  hours. 

I  do  not  know  what  conclusion  you  may  draw  from  the  data  con- 
tained in  Table  II,  but  to  my  mind  they  are  strongly  suggestive  that 
the  same  mode  of  propagation  which  we  were  making  use  of  at  Camp 
Lazear  during  the  past  winter  was  at  work  in  the  epidemic  of  yellow 
fever  at  Orwood  and  Taylor,  Miss.,  during  the  summer  of  1898. 

From  my  own  personal  experience,  I  can  only  add  one  observation 
to  those  given  by  Carter,  viz,  at  Quemados,  Cuba,  where  of  two 
nurses  who  remained  continuously  in  attendance  upon  a  case  of  yellow 
fever,  one  contracted  the  disease  on  the  fourteenth  day  and  the  other 
on  the  fifteenth  day  after  the  commencement  of  the  primary  case. 

While  the  temptation  is  great  to  extract  from  the  literature  other 
observations  confirmatory  of  those  given  (and  they  are  numerous),  I 
must  refrain  from  doing  this,  since  I  promised  to  confine  myself  largely 
to  my  own  experience  in  regard  to  the  propagation  of  yellow  fever. 
For  this  reason  and  because  I  feel  that  I  have  already  trespassed 
on  your  patience  longer  than  I  had  any  right  to  do,  I  must  omit  any 
reference  to  the  habits  of  culex  fasciatus,  or  of  the  thermal  influences 
concerned  in  the  propagation  of  this  mosquito,  both  of  which  are  of 
much  importance  in  connection  with  the  subject  under  consideration. 


108  YELLOW   FKVEB. 

I  trust  that  I  have  said  enou«:h.  however,  to  indicate  to  you  that,  in 
my  opinion,  tho  ideas  Which  we  have  heretofore  hold  oonoornim:  tho 

Propagation  of  yellow  fever  must  unden/o  oonndorahlo  rocastinir. 
do  not  believe 'that  we  can  longer  a-cribo  \\ilh  confidence  any  part 
of  the  spread  of  this  disease  to  fomitcs.  for  under  such  conditions  of 
intimato  and  lon^-continucd  exposure  as  could  never  occur  in  the 
natural  course  of  oven -day  life  \\e  have  looked  in  vain  for  its 
development. 

While  in  matters  pertaining  to  tho  public  hoalth.  cleanline^  .should 
always  stand  next  to  L'odliness.  1  do  not  think  that  we  will  bo  justified 
in  assigning  so  much  importance  hereafter  to  those  insanitary  condi- 
tion- which,  bring  due  especially  to  pollution  with  animal 
mail  -d.  in  some  mysterious  way.  to  aid  in  the  spl 
of  this  disease.  Strange  as  it  may  sound,  I  do  not  believe  that  the 
enforcement  of  the  most  rigid  hygienic  regulations,  such  as  ue  have 
heretofore  known  them,  will  nrevont  i  he  propagation  of  thi-  -rave 
epidemic  disease,  provided  it  sliould  again  bo  imported  into  this  coun- 
try. I  seriously  doubt  if  we  can  longer  class  yellow  fever  with  the 
"filth  disoa-  The  apparent  result-  obtained  by  tho  imp- 
sanitary  arrangomonts  instituted  by  Gen.  Butler  in  the  city  of  New 
Orleans,  during  the  year  1862,  and  carried  on  by  his  military 
cessore,  probably  served  to  strengthen,  as  much  as  anything  else,  the 
view  held  by  tne  profession  that  filth  was,  if  not  o-sential.  yet  of 
extreme  importance,  in  aiding  the  spread  of  yellow  fever.  I  dare 
say  that  but  few  stopped  to  consider  that  Gen.  Butler  found  the  city 
of  New  Orleans  already  quite  free  of  yellow  fever,  and  that  the  same 
system  of  blockade  which  kept  this  disease  out  of  the  former  city, 
under,  improved  sanitary  conditions,  kept  it  out  of  other  Southern 
seaports  during  the  same  period,  although  their  sanitary  conditions 
remained  unchanged.  If  one  is  inclined  to  believe  that  impi 
hygienic  conditions,  as  usually  understood,  will  arrest  the  spread  of 
yellow  fever,  let  him  turn  to  the  city  of  Habana  under  American  sani- 
tary administration.  Probably  in  no  city  in  the  world  have  such 
unremitting  sanitary  efforts  been  put  fortn  as  in  the  city  of  Habana 
since  our  occupation  in  January,  1899.  We  were  told  tliat  the  hard 
work  of  Gen.  Ludlow  and  his  assistants  was  responsible  for  the  marked 
<  locrease  of  cases  of  yellow  fever  during  the  first  seven  months  of  1899 — 
and  appearances  seem  to  indicate  as  much — nevertheless,  with  the 
commencement  of  Spanish  immigration,  during  August  of  that  \ 
and  the  introduction  of  susceptible  material,  cases  of  yellow  i< 
began  to  rapidly  multiply,  so  that  the  city  had  a  late  summer  and  fall 
epidemic  of  this  disease.  Concerning  the  occurrence  of  yellow  I 
in  that  city  during  the  past  year,  Mai.  Harvard,  chief  surgeon,  Depart- 
ment of  Cuba,  in  a  recent  report,  after  describing  the  thorough  work 
which  had  been  done  by  the  sanitary  authorities  and  its  marked  effect 
upon  the  reduction  in  deaths,  especially  from  tuberculosis,  goes  on  to 
say: 

It  is  certain  that  in  Habana,  in  1900,  no  visible  correlation  could  be  seen  between  <  1  i  r> 
and  yellow  fever;  the  district  which  became  first  strongly  infected  lies  east  and  south 
of  the  Parque  Central,  and  is  one  of  the  cleanest  and  best  constructed,  while  the  most 
insanitary  wards  became  infected  late  in  the  season  and  only  to  a  slight  extent;  i  h<- 
malodorous  district  reserved  to  houses  of  ill-fame  hardly  had  a  case.  Yellow  fev< 

I  lowed  the  poor  and  unclean,  nor  the  mark  of  previous  inf.  •«  li-.n,  but  null,  r  tin- 
movement  of  nonimmunes:  wherever  these  located,  there  the  infection  searched  and 
found  them,  regardless  of  the  hygienic  conditions  of  their  premises. 


YELLOW    FEVER.  109 

What  is  the  sanitary  story,  then,  for  the  year  1900?  Simply  that 
with  the  return  of  summer  weather  and  the  continued  influx  of  new 
material,  and  in  spite  of  unremitting  efforts  to  keep  the  city  clean, 
Habana  has  experienced  a  more  serious  epidemic  of  yellow  fever, 
affecting  its  civilian  population,  than  it  has  had  during  the  preceding 
20  years.  Need  we  now  express  surprise  at  such  a  result  ?  Have  we 
not  seen  at  Camp  Lazear,  under  the  very  best  hygienic  surroundings, 
six  individuals  attacked  with  yellow  fever,  after  a  few  short  visits  to  a 
new  building  whose  foundation  stood  on  the  unbroken  turf  and  whose 
rooms  were  filled  with  sunshine  and  with  an  atmosphere  just  swept 
in  from  the  ocean,  at  the  very  moment  of  infection?  Where  then, 
gentlemen,  shall  we  look  for  the  agent  that  is  vitally  concerned  in  the 
propagation  of  yellow  fever  ?  In  the  light  of  these  newer  observations 
which  I  have  had  the  pleasure  of  presenting  to  you,  I  believe  that  we 
may  affirm,  with  some  degree  of  confidence,  that  here,  substituting 
culex  for  anopheles,  we  have  to  deal  with  the  same  source  of  infection 
to  which  we  now  trace  the  malarial  fevers — the  mosquito. 


CHAPTER  5. 

EXPERIMENTAL  YELLOW  FEVER.' 

IU   WALTER  RF.KM.  M     !•  .  Surgeon,  United  Stairs  \rn\\      .l\v  L,  M     !>.. 

and  A.  AGRAMOSTE.  M.  D.,  Contract  Surgeon^    I  nit<d  stairs  Army. 

Subsequent  in  the  prrM-niniinn  of  our  paper  to  the  Pan-American 
Congress  :  in  llabana,  we  succeeded  in  producing  some  additional 
Cases  of  vcl low  fever  at  our  experimental  sanitary  Matimi  near  (v)u<>- 

inados,  Cuba.    We  have  thought  that  brief  reports  of  these  CMJ 

be  followed  by  remarks  on  experimental  yellow  fever  fmm  t  he  clinical 
point  of  view,  would  ho  of  interest  to  the  members  of  this  associat  inn, 
and  especially  to  those*  who  reside  in  sections  of  the  country  where 
each  year  yellow  fever  is  liable  to  apnear  in  epidemic  form. 

Perhaps  it  miirht  be  well  to  recall  the  fact  that  the  cases  of  yellow 
fever  here  to  be  recorded  were  produced  like  those  heretofore  reported 
by  us,  under  strict  quarantine  re«:ulations  and  at  a  -peeiai  experi- 
mental sanitary  -tat inn,  near  the  town  of  Quemadns.  Cuba. 

In  a  series  of  12  experimental  cases  produced  at  this  camp  during 
the  period  from  Decembers,  1900,  to  February  7.  P.Mil      an  int. 
of  65  days — it  should  be  borne  in  mind  that  the  order  <>f  occurrence 
exactly  correspond  with  the  order  of  inoculation,  except  that  Case  II. 
inoculated  at  4  p.  m.,  December  8,  1900 — having  a  longer  period  «»f 
incubation  than  Case  III,  inoculated  at  10.30  a.  in      Decemh 
1900 — the   order   of   their;  relative   occurrence   became   re\«  i 
Moreover  the  attack  always  followed  within  the  period  of  incubation 
of  the  disease,  and  concerned  only  those  nonimmune  individuals  who 
had  consented  to  submit  themselves  for  experimentation.     Of  a  total 
of  16  individuals  who  thus  consented,  14  contracted  yellow  f. 
whereas  of  5  nonimmunes,  who  did  not  consent  and  were  therel<.n 
not  subjected  to  experimentation,  none  acquired  the  d  .-dthou.irli 

otherwise  placed  under  exactly  similar  surrounding  In  it>  occur- 
rence, therefore,  at  this  station,  yellow  fever  strictly  obeyed  the 
behests  of  the  experimenters,  both  as  to  place  and  time  of  occurrence. 
Recovery  took  place  in  all  cases. 

(A)  CASES  PRODUCED  BY  (Hi  l\JH  ROM  "K  BLOOD. 

Case  I. — \V.  J.,  American,  nonimmune,  aged  27 — in  quarantine  since  December 
20,  1900— with  his  full  consent,  at  11  a.  m.,  January  4,  1901,  was  injc<  t.,1  >U!M -ut:t- 
neously  with  2c.  c.  of  blood  taken  from  the  general  circulation  "fa  case  of  mild  \«'ll«.\v 
fever  at  the  beginning  of  the  second  day  of  the  disease  and  having  a  tcin; 
100.8°  F.     The  subject,  who  had  born  in  Mriei  nu:inmiin<-  ;it  tin-  .-tati<>n  fur  tin-  ; 
of  45  days,  remained  in  his  usual  health  until  the  early  morning  of  January  8, 
he  complained  of  slight  frontal  headaches.    At  6  a.  m.  his  temperature  was  98. 
and  pulse  70;  9  a.  m.,  temperature  99.8°  F.,  pulse  95;  frontal  headache  increased,  with 

t  RMd  before  the  Sixteenth  Annual  Meeting  of  the  Association  of  American  Physicians,  held  at  Wash- 
tattoo,  April  30,  May  1  and  2, 1901. 

i  The  Etiology  of  Yellow  Fever.  An  Additional  Note.  Read  at  the  Pan-American  Con*re»,  Habana, 
February  4-7,  1001 

•  Thcac 


were  reported  In  our  Additional  Note. 
110 


YELLOW   FEVEK. 


Ill 


112  YELLOW   PE\ 

plight  chilly  sensations  in  the  foot  and  lo\\ .  Ities,    Tl  »me  con- 

gestion of  the  eyes  and  his  usual  florid  compl«'xi«-n  \\as  heightened  in  color,  At 
a.  m.,  temperature  100.6°  F.,  pulse  97.  Complains  of  some  pain  in  the  lumbar 
region.  At  1 1  JO  a.  in.,  temperature  101.4°  F.,  pulse  99.  The  height  of  the  febrile 
paroxysm  was  reached  at  3  p.  m.  the  same  day,  when  the  temperature  wa.- 
and  pulse  108.  The  facial  expression  was  now  characteristic  of  yellow  lever,  The 
eyes  were  deeply  inj<-<  tod  and  watery  and  the  face  much  suffused.  Photophobia 
moderate-  headache  and  backache  severe.  The  skin  wa  The 

remission  occurred  at  tht  ;  hours— 9  a.  m.  January  !•  ho  temperature 

had  fallen  to  99.4°  F.  and  the  pulse  to  86.  The  subsequent  history  WM  that  of  *  CM| 
of  yellow  fever  of  moderate  H  Mtnimin  was  found  in  tin-  urino  at  the  -  n<l 

of  the  sixty-first  hour.  There  was  some  bleeding  from  the  gums  on  the  third  day 
and  moderate  ocular  jaun<li«>  on  the  fourth  day.  Fever  disappeared  on  the  morning 
of  the  seventh  day.  (Chart  I.) 

Cote  II.— W.  O.,  American,  nonimmune,  aged  28,  in  quarantine  since  December 
20, 1900.    On  January  8,  1901,  at  9  p.  m.,  with  his  full  consent,  he  was  given  by 
cutaneous  injection  1.5  c.  c.  of  blood  taken  from  the  mediancrphalic  vein  of  Case  I, 
just  12  hours  after  the  beginning  of  the  attack  and  when  the  temperature  was  102  : 
that  is,  just  after  the  first  febrile  paroxysm  began  to  d<  he  subject 

in  his  usual  condition  during  the  following  two  days. 

January  11,  1901,  at  6  a.  m.  his  temperature  was  98.9°  F.  and  pulse  70.     1 1«- 
plained  of  being  disturbed  by  dreams  during  the  night  and  had  some  frontal  head 
At 9  a.  m.  temperature  100°  F.,  pulse  77.    At  10. 15 a.  m.  temperature  101.4°  F.,  pulse 
76.    Eves  decidedly  congested  and  face  moderately  suffused.    At  12  «• '« -U -k 
when  the  temperature  had  risen  to  103.2°  F.  and  the  pulse  to  10i'.  the  h.-L-ht  ..f  the 
primarv  paroxysm  had  been  reached.     Headache  and  backache  were  now  much 
complained  of.    The  facial  expression  was  characteristic.    The  r« -mi-ion  <>< -curred 
at  the  end  of  24  hours,  lasted  one  day,  and  was  followed  by  a  very  moderate  secondary 
fever.    A  distinct  trace  of  albumin  was  found  in  the  urine  passed  at  2  a.  in.  .la unary 
12,  17  hours  after  the  attack  began.    A  few  hyaline  casts  were  also  presei 
bleeding  from  the  gums  occurred  on  the  second  and  third  days  of  sickness, 
character  of  the  attack  in  this  case  was  vey  mild.    The  albumin,  which  at  no  time 
amounted  to  more  than  a  distinct  trace,  did  not  disappear,  however,  until  January 
24.     (Chart  II.) 

Case  III. — W.  F.,  American,  nonimmune,  aged  23,  was,  with  his  full  consent 
p.  m.  o'clock  January  22,  1901,  injected  subcutaneously  wit  of  blood  i 

on  the  second  day  from  the  general  circulation  of  a  severe  case  of  yellow  fever,  which 
was  fatal  on  the  seventh  day  of  the  disease.  The  patient's  ten  \\hi-n  the 

blood  was  withdrawn,  was  103°  F.  and  pulse  90.    Tne  subject  remained  well  during 
the  following  day.    January  24,  at  6  a.  m.,  his  temperature  was  98.4°  F.,  and  pulse 
78.     He  partook  of  a  hearty  breakfast  at  6.30  a.  m.,  wnich  he  vomited  soon  afterwards. 
At  7  a.  m.  he  complained  of  dizziness  and  general  lassitude.    Temperature,  98.4°, 
pulse  78.    At  9  a.  m.,  chilliness  complained  of,  but  there  is  no  record  of  toi'iperature 
or  pulse.    At  9.30  a.  m.,  temperature  100.6°  F.,  pulse  82.     Frontal  headache 
marked.     Eyes  already  injected  and  face  slightly  suffused.     At  10.30  a.  m 
ture  101.2°  F.  and  pulse  86.    An  hour  later  his  temperature  was  102.6°  F.  and  \ 
82.    The  height  of  the  primary  paroxysm  was  reached  at  1  p.  m    win -n  the  ter 
ture  was  102.8°  F.  and  pulse  98/    At  this  hour  photophobia  was  well  marked  mid 
constant  complaint  made  of  severe  frontal  headache  and  backache,  together  with 
pains  in  the  lower  extremities.    The  skin  was  moist.    The  mm  it  tin- 

end  of  36  hours.    The  subsequent  course  was  that  of  a  case  of  yell  '.rate 

severity.    With  the  return  of  the  secondary  fe\  •  -r  there  \v«  •>••  sharp  backache 

and  headache.  Albumin  appeared  in  the  urine  at  the  end  of  57$  hours.  Ocular 
jaundice  was  present  on  the  tnird  day  and  thereafter  unt  il  convalescence.  The  ^mm 
did  not  bleed,  although  they  were  swollen  and  injected  .l»-id«-d  mi  th. 

day,  and  albumin  disappeared  on  the  eighth  day.     (Chart  1 1 1   > 

Case  IV. — J.  H.  A.,  American,  nouimmuno,  aged  22,  with  hi-<  full  OH 


January  26  and  27,  except  that  on  the  afternoon  ..f  the  laM-memmned  date  h. 
plained  of  occipital  headache.    This  was  present  on  the  following  morning,  January 
28;  otherwise  he  felt  well.    His  temperature  at  noon  was  98.6°  F.,  and  pulse  68. 
Occipital  headache  continued.    He  partook  of  dinner  with  fair  appetite.    He  was  not 
seen  again  until  3  p.  m.    In  the  meanwhile,  at  1.15  p.  m.,  the  subject  states  that 
while  sitting  alone  in  his  tent,  he  began  to  feel  cold,  and  that  this  was  quickly  fol- 
lowed by  a  decided  chill  with  increase  of  headache.    He  noted  the  hour  in  writing  at 


YELLOW   FEVER. 


118 


79965°— S.  Doc.  822,  61-3 8 


114  YELLOW  FEVBB. 

the  time.  At  3  p.  m.  his  temperature  was  103.6°  and  pulse  120.  The  eyes  were 
intensely  congested  and  the  face  deeply  suffused.  The  patient  was  very  restless ,  and 
complained  bitterly  of  occipital  headache  and  backache.  Photophobia  waf 
marked.  He  vomited  several  times  within  the  next  2  hours.  Skin  hot  and  dry. 
The  height  of  the  primary  paroxysm  was  reached  at  3.30  p.  m.,  at  which  h.-ur  tin- 
temperature  was  104.2°  P.,  and  pulse  120.  The  subsequent  history  was  on 
yellow  fever.  There  was  no  remission  in  the  fey.  r  until  the  fourth  day.  \\hcn  the 
temperature  fell  to  101.2°  F.  Now,  for  the  first  time,  the  patient  ceased  to  complain 
of  occipital  headache  and  backache.  Albumin  appeared  at  the  end  of  18}  hours 
(7.30  a.  m.,  January  29).  A  few  hyaline  casts  were  also  present  at  this  time.  I  h« 
specii  ne  passed  at  6.40  a.  m.,  January  30,  contained  albumin  onc-t \\vnt icth 

by  volume,  and  many  fine  and  coarse,  granular,  bile-tinted  casts.    Ocular  jaundice 
appeared  on  the  third  day.    The  skin  ot  the  face  and  of  the  anterior  part  of  t  li- 
ana thorax  was  tinted  on  the  fourth  day.    This  rapidly  became  intensified  a : 
The  secondary  fever  lasted  about  30  hours.  th»>  tcnijicraturc  falling  to  97.2°  F.  at  rj 
o'clock  (midnight)  «.f  the  tilth  day.    Marked  fluctuations  of  temperature  o.niinued 
until  the  eleventh  day  of  illness.    Recovery  was  slow  and  much  delayed  l>y  the 
•pment  of  a  carbuncle  in  the  left  sacral  region.    A  trace  of  albumin  was  still 
present  on  March  1,  32  days  after  the  attack  had  begun.    (Chart  IV.) 

The  production  of  yellow  fever  by  the  injection  of  blood  tak<  -n 
from  the  general  circulation  is  of  much  interest  as  showii 
that  the  parasite  is  present  in  the  blood,  at  least  during  the  early 
stages  of  the  disease,  and  secondly,  that  its  passage  through  an  i 
mediate  host,  although  this  would  seem  to  be  nature's  met  1m. I,  is  not 
essential  in  the  life  cycle  of  this  parasite.     Thus  yellow  fever  is 
analogous  to  the  malarial  fevers,  in  that  it  may  be  produced  either 
by  the  bite  of  a  certain  species  of  mosquito,  or  by  the  injection  of 
blood  taken  directly  from  the  general  circulation. 

Another  point  to  which  we  nave  elsewhere  referred,  but  which  is 
considered  of  sufficient  importance  to  bear  repetition  lien-,  is  that  in 
each  of  the  foregoing  cases  of  experimental  yellow  fever  pro* lured  by 
the  injection  of  blood,  careful  cultures  made  from  the  same  blood 
drawn  from  the  vein  immediately  after  injection  or,  as  in  one  instance, 
made  from  the  same  syringeful  of  blood  that  conveyed  the  disease, 
failed  to  show  the  presence  of  Sanarelli's  bacillus.  In  one  case  colo- 
nies of  Staphylococcus  pyogenes  citreus  were  obtained,  while  in  the 
remaining  three  cases  no  growth  whatever  occurred.  The  exclusion 
of  Bacillus  icteroides  from  further  consideration  as  the  specific  a  ji  1 1 1  of 
yellow  fever  would,  therefore,  seem  to  have  been  conchiMvely  <; 
mined  by  these  experiments. 

(B)   CASES   PRODUCED    BY   THE    BITE    OF  THE    MOSQUITO,  CULEX    FA8CIATU8. 

Case  V. — L.  F.,  American,  nonimmune,  aged  28 — in  quarai  .or  20, 

1900— was,  with  his  full  consent,  at  3. 30  p.m. ,  January  l!i,  l!»in,  hi  tu-n  by  three  mos- 
quitoes that  had  been  contaminated  39  aays  previously,  by  feeding  on  the  blood  of  a 
well-marked  case  of  yellow  fever,  on  the  third  day  of  the  disease.  The  subject 
remained  in  his  usual  condition  of  health  until  the  afternoon  of  January  on  of 

this  date  his  temperature  was  97.8°.  Soon  after  this  hour  he  took  to  his  bed,  com- 
plaining of  frontal  headache  and  general  lassitude.  At  3  p.  m.  his  temperature  was 
99.2°  and  pulse  78.  At  4. 10  p.  m.  the  temperature  was  100°  F.  and  pulse  104.  A 
sense  of  chilliness,  especially  of  the  lower  extremities,  and  increased  frontal  headache, 
were  now  complained  of.  Eyes  already  injected  and  face  flushed.  At  5  p.  m.  th«- 
temperature  was  101.2°  F.  and  pulse  104.  The  height  of  the  paroxysm  was  \ 
8.20  p.  m.,  at  which  hour  the  temperature  was  103.6°  F.  and  the  pulse  IK).  The  eyes 
were  deeply  congested  and  photophobia  very  marked.  Headache  and  back 
so  intense  as  to  cause  the  patient  to  complain  bitterly.  He  vomited  once  at  9  p.  m. 
January  24, 3  a.  m.,  the  temperature  had  (alien  to  100.2°  and  the  pulse  to  104,  hut  \\  ii  h 
only  slight  amelioration  to  the  patient's  discomforts.  At  noon  the  thermometer 
marked  102°.  Remission  occurredat  the  end  of  33  hours,  with  marked  diminution  of  all 
disagreeable  symptoms.  The  secondary  fever,  attended  by  increased  headache  and 


YELLOW    FEVER. 


115 


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116  YELLOW   FEVER. 

backache,  lasted  four  days,  the  temperature  dropping  to  normal  at  6  p.  m.  of  the 
seventh  day.  The  case  was  one  of  moderate  severity.  Albumin  a;  p«-ared  in  the 
urine  at  the  end  of  the  forty-second  hour.  'Ocular  jaundice  was  quite  noticcai 
the  afternoon  of  the  second  day.  Some  jaundice  of  the  face  and  an  ten  r  ••-  -i-n  «f  the 
chest  was  seen  on  the  fourth  day.  Many  bile-tinted  granular  casts  were  present  in  the 
urine  on  the  third  day.  and  thereafter  until  the  eleventh  day.  The  albumin  which 
reached  one-fifteenth  by  volume  on  the  sixth  day  disappeared  on  the  twelfth  day. 
(Chart  V.; 

Cote  VI. — C.  W.,  American,  nonimmune,  aged  -7.  with  his  full  consent,  was  at 
9.30  a.  m.,  January  31,  bitten  by  2  of  the  3  mosquitoes  that  had  been  applied  t<>  the 
foregoing  Case  V.    The  interval  that  had  elapsed  since  their  contamii 
therefore,  51  davs.    The  subject  remained  well  until  in  o'clock  noon.  I-Vhru. 
when  he  complained  of  heaviness  in  his  legs  and  some  supraorbital  pain 

ire  at  this  hour  was  99°  F.  and  pulse  70.    At  1.30  p.  m.  it  had  ri-  n  to  UK)0  F., 
and  at  5  p.  m.  to  100.°  F.  and  pulse  to84.    The  primary  risepf  fever,  which  was 
what  fluctuating  in  character,  did  not  reach  its  height  until  at  the  <  n  )  .1  j;  • 
noon,  February  1,  when  the  temperature  was  102.4°  and  the  pulse  92. 
was  now  suggestive  of  yellow  fever.    Remission  occurred  at  the  end  of  J~>  hours  and 
lasted  for  about  1  day.    The  secondary  rise  was  slight  in  char.it -t. -r,  the  temperature 
falling  to  normal  on  the  morning  of  the  sixth  day.    The  case  was  very  mild  in  <  har 
acter.    Albumin  appeared  at  the  end  of  75  hours  (beginning  of  fourth  day 
amounted  to  more  than  a  distinct  trace  and  disappeared  on  the  eighth  da; 
was  no  ocular  jaundice,  and  although  the  gums  were  injected  and  swollen,  there  was 
no  hemorrhage  at  any  time.    The  patient  perspired  freely  throughout  the  at 
Convalescence  was  rapid.    The  subject  had  been  in  quarantine  for  the  period  of  6 
days  prior  to  inoculation.     (Chart  Y  I 

Case  VII.— J.  H.,  American,  nonimmune,  aged  26,  with  his  full  consent,  was  bitten 
at  11  a.  m.,  February  6,  1901,  by  the  same  2  mosquitoes  that  had  6  <i 
bitten  Caso  VI.     Fifty-seven  days  had  therefore  elapsed  since  the  insects  had 
contaminated  by  biting  a  case  of  yellow  fever.    He  remained  well  until  IL'  • 
noon,  February  9,  when  he  experienced  slight  chilly  sensations,  accompanied  by 
yawning.    At  this  hour  his  temperature  was  99°  F.  and  pulse  72.    At  :>  p.  m  .  t. ni 
perature  98.8°,  pulse  72.    Says  mat  he  feels  "out  of  sorts,    but  has  no  \  i 

5. 30  p.  m.  his  temperature  was  100.6°  F.,  pulse  78.    He  was  not  seen  until  7 .:><)  p.  m  , 
when  he  complained  of  backache  and  severe  general  headache,  mon-  intense  through 
the  frontal  region.    Eyes  much  injected,  photophobia  very  marked,  fa<  e  \\\; 
He  was  stretching  and  yawning  constantly,  complained  of  nausea,  and  vom: 
small  quantity  of  partially  digested  food.     The  height  of  the  primary  fever  was  reached 
at  3  p.  m.,  February  10,  i.  e.,  22  hours  after  the  commencement  of  the  attack,  when 
the  temperature  was  102.8°  and  the  pulse  98.     Remission  of  th-  and 

pulse  to  74  occurred  at  6  a.  m.,  February  11,  making  the  duration  of  the  primary 
paroxysm  36  hours.    Twenty-four  hours  after  the  remission  had  occurred  the 
perature  had  risen  to  102.4°  with  a  pulse  of  70.    The  fever  continued  to  steadily 
increase  until  midnight  of  February  12,  when  a  temperature  of  105°  F.  was 
with  a  pulse  of  90.    The  subsequent  course  was  that  of  a  case  of 
Slight  oozing  of  blood  from  the  gums  occurred  as  early  as  the  third  da 
jaundice,  beginning  on  the  third  day,  became  later  very  distinct  and  was  associated 
with  general  jaundice.    Albumin,  however,  did  not  appear  until  the  sixth  day.     The 
fever  subsided  on  the  ninth  day,  and  was  followed  by  a  slow  convalescence.    The 
subject  had  been  in  strict  quarantine  for  a  period  of  78  days  prior  t.>  in<>< -illation. 
(Chart  VII.) 

Case   VIII. — C.  S.,  American,  nonimmune,  aj/«  fh  his  full  con 

bitten  at  2  p.  m.,  February  7,  1901,  by  3  mosquitoes  that  had  been  « ••mtamr 
16  days  previously  by  biting  a  fatal  case  of  yellow  fever  on  the  second  day  of  the 
disease.    The  subject  remained  well  until  the  early  afternoon  of  the  third  day. 
ruary  10.    He  ate  his  dinner  at  noon  with  good  app«  i  it <       At  I  p.  m.f  hiatempentan 
was  100°  F.,  pulse,  90.     Frontal  headache  was  now  complained  of.    Tl 
rapidly  more  marked,  and  pains  in  the  limbs  were  also  present.    Three  hours  later. 
4  p.  m.,  the  fever  had  risen  only  one-lift  h  of  a  d.-.-n-c,  but  at  <i  p.  in.  it  had  re;. 
103°  F.  and  pulse,  96.    At  this  hour  he  had  severe  headache  and  backache,  with 
general  pains  over  the  body.    The  facial  expression  was  now  characteristic.    Eyes 
brightly  injected,  photophobia  well  marked,  and  face  decidedly  congested.    At  9 
p.  m.  temperature  was  103.2°  and  pulse  1 12.    The  skin  was  moist.     Remission  occurred 
at  6  a.  m.,  February  12,  41  hours  after  the  commencement  of  the  febrile  paroxysm. 
The  secondary  fever,  which  was  moderate  in  character,  lasted  4  days,  the  i.  \<  r  sub- 
siding on  the  seventh  day.    Ocular  jaundice  was  slight.    A  few  hyaline  casts 
present  on  the  third  and  subsequent  days,  but  no  albumin  was  found  until  1  p.  m., 


YELLOW   FEVER, 


117 


118  x>  ii. LOW  FF.vn:. 

1-Vt.ruary  18,  that  is,  36  hours  aiu-r  th«>  tVvrr  luul  sul>Mu«-a.  It  was  present  at  a  <lis- 
tiurt  trace  in  all  specimens  examined  until  3  p.  m.,  February  23.  i  '«>:  was 

rapid.  The  subject  had  been  in  quarantine  for  a  period  of  25  days  prior  to  inocula- 
tion. (Chart  VIII.) 

The  foregoing  cases  of  experimental  yellow  fe\  \  .  V 1 .  and 

VI 1  are.  we  think,  of  especial  importunes  asshowing  thelenirt  h  of  time 
during  \vhirh  the  mosquito  may  remain  capableof  convex -in.ir  the  infec- 
tion. In  previous  papers  \ve  have  reported  (i  cases  of  yeil..\\  fever  pro- 
duced by  tlie  bitonf  m. »(|iiitos  at  intervals  varying  from  1  -  t«»  _  1  days 
after  the  contamination  of  the  insects.  In  the  ca>es  here  reported 
tiie  periods  intervening  between  the  contamination  of  the  insect  and 
the  production  of  the  disease  were  much  longer.  '.  51,  and  :>7 

day-,  respectively.  As  one  of  the-e  injects  lived  until  the  sixty-ninth 
and  another  until  the  seventy-first  day  after  contamination.  we  have 
for  the  iiist  time  an  explanation  of  the  fact,  several  times  noted  in 
the  literature,  that  the  omtagion  of  yellow  fever  may  cling  foi 
months  to  a  building  that  has  been  vacated  by  its  occupants,  or  to 
the  infected  area  of  a  town,  even  though  this  latter  h;:s  been  entirely 
depopulated.  These  particular  insects  also  \\eiv  contaminated  at  a 
hit  erst  age  of  the  disease  than  in  any  of  our  other  cases,  i.  e..on  the  third 
day  and  during  the  secondary  rise  of  the  fever,  following  a  complete 
intermission  in  the  temperature.  We  have,  therefore,  been  able  to 
demonstrate  that  the  parasite  is  present  in  the  general  circulation 
both  after  and  before  the  stage  of  remission.  How  much  later  in  the 
disease  the  parasite  may  stifl  be  found — a  matter  of  much  int. 
and  importance — the  observations  thus  far  made  do  not  determine. 
Although  the  3  mosquitoes  applied  on  the  third  day,  as  above  stated. 
acquired  the  parasites  and  were  able  to  affect  3  individuals  with  yellow 
fever,  a  single  mosquito  applied  to  the  same  case  of  yellow  fever  on 
the  fourth  day  of  the  disease  failed  to  obtain  the  parasite,  as  sho\\n 
by  the  negative  result  following  its  bite  40  days  after  contamination. 
That  not  all  mosquitoes  become  infected,  however,  with  the  parasite 
by  bitingyellow  fever  patients  is  shown  by  several  observat i» >ns  made 
by  us.  We  submit  only  one. 

Case  IX. — J.  W.,  American,  nonimmune,  was,  with  his  full  r<ms«-nt.  mi  January 
25,  1901,  bitten  by  12  mosquitoes  (C.fasciatus)  that  had  fed  on  a  il«l  \vlln\\- 

fever — in  a  man  named  Martinez — on  January  3,  1901,  within  8  hours  of  the  com- 
mencement of  the  attack.  Although  these  mosquitoes  had  been  kept  at  a  summer 
temperature  for  22  days,  the  result  of  the  experiment  was  entirely  nc-aiivr.  Thai 
the  parasites  were  present  in  Martinez's  blood  at  the  end  of  24  hours  was  fully  nhown 
by  tne  effect  produced  by  injecting  2  c.  c.  of  his  blood  drawn  at  this  time  beneath  the 
skin  of  Case  I  of  this  report. 

Observations  such  as  the  foregoing  would   indicate  that  the  mos- 
quito at  certain  periods  of  the  disease  may  fail  to  obtain  the  parasite, 
owing  to  its  absence  at  that  particular  time  from  the  capillary  circu- 
lation.    Concerning  the  matter  of  the  propagation  <>f  yellow   t 
by  other  species  of  culex  than  C.  fasriatus,  we  have  only  1  negative 
observation  to  record  of  an  individual  bitten  by  5  C.  pungens  that 
had  been  contaminated  by  biting  a  case  of  yellow  fever  in  days  pre- 
viously.    To  a  single  negative  experiment  such  as  this  no  importance 
can  be  given,  so  that  this  question  must  be  left  for  future  obfl 
tions  to  determine. 

Touching  the  subject  of  the  possible  transmission  of  the  parasite 
to  the  daughter  insect  by  means  of  infection  of  the  ovum,  we  have 
also  but  a  single  observation  to  record.  In  this  case  the  bites  of  14 


YELLOW   FEVER. 


119 


120  .A'W    WM\ 

mosquitoes,  hatched  from  the  ova  of  a  mosquito  (C.fascialu^  that  had 
already  shown  itself  capable  of  conveying  the  disease,  were  followed 
by  an  entirely  negative  result. 

'Including  the  cases  heretofore  reported  by  us,  we  have  thus  far 
siu veeded  in  conveying  yellow  fever  to  12  individuals  by  means  <>f 
the  bites  of  contaminated  mosquitoes,  and  to  4  other  persons  by  sub- 
cutaneous injection  of  blood  taken  from  cases  of  this  disease — a 
total  of  16  cases.  While  ordinarily  so  small  a  number  of  cases  would 
l>e  sufficient  to  enable  one  to  arrive  at  definite  conrlu-i-'Hx  con- 
cerning the  general  character  and  course  of  an  acute  infection- 
disease,  the  conditions  under  which  the  majority  of  these  en 

observed    were    such    as    to    jrive    us    valuable    data    miK-eni'mi:    twn 
matters  of  very  great  practical  importance  in  connection  with  this 
disease,  viz,  the  period  of  its  incubation  and  the  difference  in  d< 
in  the  character  of  it-  attacks.     Further,  as  these  caa 
under  constant  observation,  even  from  the  time  of  inoculation,  \N«- 
are  not  only  able  to  report  upon  the  earlie-t  j>n -monitory  svmntnm-. 
but  also  to  give  the'pnmary  temperature  curve;  and,  in  addition,  t<> 
note  the  time  of  appearance  of  Albumin  in  the  urine,  all  of  whie! 
of  interest  in  the  clinical  history  of  yellow  fever. 

Period  of  incubation. — The  accurate  determination  of  the  period 
of  incubation  of  any  one  of  the  acute  infectious  diseases  is  always  a 
matter  of  scientific  interest.  If  the  disease  is  one  which,  like  yellow 
fever,  is  of  exotic  origin  and  whose  importation  is  liable  to  give 
to  a  widespread  epidemic,  then  the  determination  of  its  incubati\<- 
stages  becomes  of  the  highest  practical  importance.  This  import  ;> 
as  a  Question  of  public  hygiene,  is  increased,  if  as  recent  observations 
, would  seem  to  indicate,  the  importation  of  this  disease  is  brought 
about  only  by  the  sick  individual  and  not  bv  his  baggage  or  clothing. 
While  the  older  authors  were  willing  to  prolong  the  period  of  incuba- 
tion of  yellow  fever  to  2  or  3  weeks  or  even  longer,  the  tendency  of 
physicians  at  the  present  time  is  to  shorten  this  stage  to  about  5  days. 
Reference  to  a  few  of  the  later  text-books  on  the  Practice  of  Medicine 
will  sufficiently  indicate  this.  Davidson,  in  Allbutt's  System,1  puts 
down  the  period  of  incubation  as  "ranging  between  24  hours  and  \ 
or  5  days.  Stevens 2  says  that  it  may  vary  from  "  a  few  hours  to  a 
week."  Osier8  says  that  "the  period  of  incubation  is  usually  3  or  4 
days,  but  it  may  be  less  than  24  hours  or  prolonged  to  7  days." 
According  to  Tyson,4  "yellow  fever  has  a  period  of  incubation  of 
from  24  hours  to  5  days,  very  rarely  exceeding  the  latter."  Stern- 
berg  5  says  that  this  period  "does  not  usually  exceed  4  or  5  days  and 
may  be  less  than  24  hours."  Carter,'  in  a  recent  valuable  paper, 
gives  the  results  of  his  studies  on  the  period  of  incubation  of  yellow 
fever,  based  on  observations  extending  over  a  considerable  number 
of  years.  Under  Class  III  of  his  observations,  which  are  the  most 
valuable,  he  includes  "those  persons  who,  living  in  a  clean  environ- 
ment, go  into  an  infected  one,  stay  only  a  short  time,  and  t  lien  ret  urn 
to  a  clean  environment  where  they  remain  until  the  fever  develops." 

»  A  System  of  Medicine,  London,  1807,  Vol.  II.  p.  394. 

•  Practice  of  Medicine.  Philadelphia,  1808,p.  286. 

•  The  Practice  of  Medicine,  New  York,  1800,  p.  185. 
«  Practice  of  Medicine,  Philadelphia,  1000.  p.TJ5. 

•Buck'*  Reference  Handbook  o?  the  Medical  Sciences,  1880,  Vol.  Ill,  p.  58. 

•  The  Period  of  Incubation  of  Yellow  Fever,  New  York  Medical  Record,  March  0, 1001. 


YELLOW   FEVER. 


121 


1 

70 


I 


122 


YELLOW   FEVER. 


123 


Of  12  cases  thus  accurately  observed  by  himself  the  incubative  stage 
was  as  follows: 


Cases. 

Days' 
incuba- 

tion. 

2 

3 

6 

3+ 

2 

4 

1 

$ 

12 

The  following  table  gives  the  result  of  our  observations  in  16  cases 
of  experimental  yellow  fever. 

TABLE  I. — Period  of  incubation  of  experimental  yellow  fever. 


No.  of 

case. 

Date  of  inoculation. 

Method  of  inocu- 
lation. 

Date  of  commencement  of 
attack. 

Incubation 

1 

\ug.  27  1900  2  p.  m 

Mosquito 

Aug.  31  1900,  9  a.  m 

Dys.  hrs. 
3      7 

2 

Aug.  31,  1900,  11  a.  m 

.  .do 

Sept.  6,  1900,  1  p.  m  

6      2 

3 
4 

Dec.  5,  1900,  2  p.  m  
Dec.  8,  1900,  4p.m.. 

do  

.  .do  ... 

Dec.  8,  1900,  11.30  p.  m  
Dec.  14,  1900,  9  a.  m  

3      9} 

5    17 

5 

Dec.  9,  1900,  10.30  a.  m 

do 

Dec.  12,  1900,  9.30  p.  m 

3    Hi 

6 

Dec.  11,  1900,  4.30  p.  m... 

.  .do.... 

Dec.  15,  1900,  12  noon  

3    19i 

7 

Dec.  21,  1900,  12  noon 

do 

Dec.  25,  1900,  11  a.  m 

3    23 

8 

Dec.  30,  1900,  11  a.  m    . 

..    .do  

Jan.  3,  1901,  10.30  a.  m  

3    22i 

9 

Jan.  4,  1901,  11  a.  m 

Blood  injection 

Jan.  8,  1901,  9  a.  m 

3    22 

10 

Jan  8  1901  9pm 

do 

Jan  11  1901  9  a.  m 

2    12 

11 

Jan.  19,  1901,  3.30  p.  m 

Mosquito 

Jan.  23,  1901,  3  p.  m 

3    23i 

12 

Jan.  22,  1901,  1  p.  m  .     . 

Blood  injection.  .. 

Jan.  24,  1901,  9  a.  m  

1     19" 

13 

Jan.  25,  1901,  12.15  p.  m 

do 

Jan.  28,  1901,  1.15  p.  m  ... 

3      1 

14 

Jan.  31,  1901,  9.30  a.  m  

Mosquito  

Feb.  3,  1901,  12  noon  

3      2i 

15 

Feb.  6,  1901,  11  a.  m 

do 

Feb.  9,  1901,  5  p.  m 

3      6 

16 

Feb.  7,  1901,  2  p.  m  

do  

Feb.  10,  1901,  12  noon  

2    22 

The  average  period  of  incubation  of  the  16  cases  embraced  in 
Table  I  will  be  round  to  be  87 \  hours,  or  3  days  15  J  hours.  If  we 
separate  the  12  mosquito  infections  from  the  4  cases  produced  by  the 
injection  of  blood,  we  have  for  the  former  a  period  of  incubation  of 
94  hours  or  3  days  and  22  hours,  and  for  the  latter  an  incubative 
stage  of  67^  hours,  or  2  days  19J  hours.  The  average  period  of  incu- 
bation, therefore,  in  the  cases  brought  about  by  subcutaneous  injec- 
tion of  blood  was  shorter  by  26^  hours  than  those  occasioned  by  the 
mosquito's  bite.  By  the  former  method,  this  stage  varied  from  43 
hours  to  94  hours,  while  in  the  mosquito  infections  the  shortest  incu- 
bative period  was  70  and  the  longest  146  hours.  If  we  accept  those 
cases  produced  by  the  mosquito's  bite  as  the  usual  method  of  propa- 
gation of  this  disease,  it  will  be  observed  that  of  the  12  cases  1  occurred 
on  the  third  day,  9  on  the  fourth  day,  1  on  the  sixth  day,  and  1  at 
the  beginning  of  the  seventh  day  after  incubation. 

While  our  results,  therefore,  confirm  the  statement  of  later  writers 
that  the  period  of  incubation  of  yellow  fever  does  not  usually  exceed 
4  or  5  days,  they  also  seem  to  indicate  very  plainly  that  this  stage 
may  be  prolonged  more  frequently,  perhaps,  than  had  been  supposed. 

In  16.6  per  cent  of  our  cases  the  period  of  incubation  exceeded  the 
usual  quarantine  period  of  5  days.  If  we  add  Carter's  cases  to  those 
observed  by  us,  we  find  that  of  24  cases  the  period  of  incubation 


124 


YKLLUW    KKVKK. 


I    i 


I 


YELLOW   FEVER.  125 

exceeded  5  days  in  3,  or  12.5  per  cent.  We  will  not  further  dwell 
on  this  subject  than  to  remark  that  cases  No.  2  and  No.  4  of  our  series 
could  have  passed  quarantine  on  the  morning  of  the  sixth  day 
after  inoculation,  with  a  clinical  thermometer  under  the  tongue,  with- 
out exciting  any  suspicion  by  reason  of  the  presence  of  fever. 

Character  of  the  attack. — We  desire  to  call  attention  particularly  to 
the  difference  in  the  degree  of  severity  of  the  attack  as  shown  by  our 
experimental  cases.  Like  all  of  the  other  acute  infectious  diseases, 
we  have  reason  to  expect  that  yellow  fever  will  affect  different  indi- 
viduals according  to  their  individual  susceptibilities,  and  hence  that 
we  will  encounter  mild  as  well  as  severe  cases.  The  results  which 
we  have  obtained  confirm  this  expectation.  Based  upon  the  char- 
acter of  the  attack,  the  12  cases  due  to  mosquito  inoculation  may  be 
divided  as  follows: 

Severe i 2 

Moderately  severe 6 

Mild 3 

Very  mild 1 

12 

The  4  cases  produced  by  the  injection  of  blood  gave  the  following 
result : 

Severe 1 

Moderately  severe 2 

Mild..  1 


Thus  the  cases  which  were  mild  or  very  mild  in  character  consti- 
tuted 33  per  cent  of  those  infected  by  the  mosquito's  bite  and  25  of 
those  produced  by  blood  injection.  It  is  to  the  diagnosis  of  the  former 
cases  that  we  desire  to  direct  special  attention.  To  one  familiar  with 
yellow  fever,  or  even  to  one  unfamiliar  with  its  clinical  features,  the 
diagnosis  of  our  severe  and  moderately  severe  cases  should  have  pre- 
sented no  difficulty.  The  sharp  headache  and  backache,  the  charac- 
teristic facies,  the  ocular  jaundice,  together  with  the  presence  of  albu- 
min in  the  urine,  except  in  1  case  to  be  hereafter  referred  to,  with  the 
negative  result  of  a  blood  examination,  would  have  been  a  sufficient 
complex  of  symptoms  to  have  rendered  the  diagnosis  tolerably  certain. 
Even  in  our  3  "mild"  cases,  were  the  physician  on  his  guard  and 
acquainted  with  the  temperature  curve  and  pulse  from  the  very  onset 
of  the  attack  and,  besides,  careful  in  the  testing  of  each  specimen  of 
urine  passed,  a  diagnosis  of  yellow  fever  could  have  been  made  with 
reasonable  probability.  We  believe,  however,  that,  in  the  ordinary 
course  of  events,  where  there  was  no  reason  to  suspect  the  presence 
of  yellow  fever  the  average  practitioner  would  have  probably  failed 
to  appreciate  the  true  nature  of  these  attacks.  Such  was  the  admis- 
sion which  we  ourselves  were  compelled  to  make,  although  in  con- 
stant attendance  and  thoroughly  acquainted  with  these  cases  from 
their  very  beginning.  The  short  duration  of  the  primary  fever  in  one 
instance;  the  rapid  amelioration  of  the  earlier  symptoms  in  all;  the 
absence  of  albumen  during  the  first  3  days,  or  its  presence,  as  a  mere 
trace,  in  certain  specimens,  followed  by  its  absence  in  succeeding 
specimens;  the  slight  icteroid  hue  of  the  conjunctiva — to  be  obtained 
only  in  a  certain  light  and  then  doubtfully — all  served  to  render  a 


126  YELLOW   FEVER. 

khre  diagnosis  exceedingly  dilheult.  Several  physicians,  who  saw 
these  milder  cases  at  our  request,  readily  acknowledged  the  improba- 
bility of  a  coirect  diagnosis  berni:  made  in  tlie  absence  of  the  complete 
data  which  we  were  able  to  furnish  concerning  them.  In  the  one  . 
which  we  have  classed  as  "very  mild"  yellow  fever  we  believe  that 
the  matter  of  a  correct  diagnosis  would  have  been  in  the  highest  de- 
gree improbable.  The  attack  consisted  of  a  single  paroxys 
hours'  (fcmtion.  during  which  the  temperature  only  reached  II 
period  of  6  hours.  It  is  true  that  albumin  was  found  in  the  urine  at 
the  end  of  :>7  hours,  but  the  quantity  was  exceedingly  small  and  only 
to  be  detected  by  the  most  delicate  testing.  It  was  only  present  in  I 
or  2  specimens  passed  on  the  third  day.  A  slight  trace  was  piv-mt  in 
a  specimen  passed  at  9  a.  m.  of  the  fourth  day  and  in  that  passe.  1  at 
4.40  p.  m.  of  the  fifth  day.  Intervening  specimens  of  urine,  several  in 
number,  contained  no  albumin.  A  weft-marked  papular  eruption 
which  appeared  on  the  fourth  day  of  the  disease,  and  which  was  « -on- 
fined  to  the  trunk  and  arms,  would  hardly  have  rendered  the  diag- 
nosis easier.  We  suppose  that  during  the  prevalance  of  an  epi<! 
of  yellow  fever  a  physician  who  was  thoroughly  acquainted  \\  ith  the 
several  types  of  this  disease  would  probably  class  tnis  case  as  one  of 
extremely  mild  yellow  fever,  with  a  wide  margin  for  doubt.  Under 
all  other  circumstances  we  feel  confident  that  cases  of  this  character 
would  escape  diagnosis.  That  cases  of  mild  yellow  fever  may  and  do 
serve  as  foci  for  the  development  of  other  cases  our  own  observations 
demonstrate,  since  we  have  been  able  to  propagate  the  disease  from  one 
such  mild  case  by  means  of  the  bites  of  contaminated  im>s<juitoi>.  -ind 
from  another  case  of  like  character  by  the  subcutaneous  injection  of 
2  c.  c.  of  blood. 

THE   ONSET   AND   PREMONITORY   SYMPTOMS. 

Of  the  12  cases  produced  by  mosquito  inoculation,  the  onset  was 
sudden  in  2  and  gradual  in  10.  In  both  of  the  former  the  attack 
occurred  during  the  night,  the  patient,  also,  in  both  instance-,  IM-HILT 
awakened  by  the  occurrence  of  a  decided  chill.  In  1  of  the  2  cas. 
sudden  onset,  the  subject  complained  of  slight  supraorbital  headache 
during  the  afternoon  preceding  the  attack.  Of  4  cases  produced  by 
the  injection  of  blood,  the  onset  was  sudden  in  1 — the  only  case 
marked  by  a  chill — and  gradual  in  3.  The  attack  in  all  of  i 
blood  cases  began  during  the  daytime.  As  writers  generally  state 
that  in  yellow  fever  the  chances  of  infection  are  greater  during  the 
night,  we  have  thought  that,  perhaps,  the  time  of  inoculation  of  our 
experimental  cases  (which  was  during  the  day  except  in  1  ii 
might  have  had  some  influence  upon  their  occurrence,  as  a  rule, 
during  the  daytime.  If  the  hour  of  inoculation  in  all  of  our  cases 
should  have  taken  place  at  about  sunset,  then,  with  the  same  period 
of  incubation,  7,  or  43  per  cent  would  have  experienced  their  attacks 
at  night. 

Of  the  13  cases  in  which  the  onset  was  gradual — by  mosquito 
inoculation,  10;  by  blood  injection,  3 — frontal  headache,  the  pain 
being  referred  to  the  supraorbital  region  and  extending  into  the 
temporal  region,  was  the  most  frequent  premonitory  symptom.  It 
was  present  in  10  and  absent  in  3  cases.  This  symptom  preceded 
the  attack  in  these  cases  at  intervals  varying  from  2  to  48  hours. 


YELLOW   FEVER.  127 

In  2  cases  no  premonitory  headache  was  complained  of,  while  in  1 
case  occipital  headache  preceded  the  onset  by  24  hours,  and  con- 
tinued to  be  of  this  character  throughout  the  attack.  Dizziness  was 
complained  of  by  3  of  the  gradually  developing  mosquito  cases,  and 
a  sense  of  weight  in  the  lower  extremities  by  the  2  others  belonging 
to  this  group.  All  of  the  cases  of  gradual  onset  (13  in  number)  com- 
plained of  lassitude  and  want  of  appetite,  on  which  account  all  took 
to  their  beds  prior  to  the  onset  or  fever.  Ten  of  these  individuals 
complained  of  slight  sensations  of  chilliness — generally  confined  to 
the  lower  extremities — at  the  beginning  of  the  attack,  while  in  3 
this  symptom  was  entirely  absent.  In  our  experimental  cases, 
therefore,  frontal  headache  and  muscular  debility  were  the  most 
frequent  and  prominent  premonitory  symptoms.  After  the  attack 
had  developed,  the  symptoms  correspond  to  those  described  at 
length  by  various  writers  and  with  which  all  are  familiar,  except  that 
black  vomit  did  not  occur  in  any  of  our  cases. 


THE    FEVER. 


As  we  have  had  prepared  charts  of  our  several  cases  of  experi- 
mental yellow  fever,  from  which  all  the  data  concerning  temperature 
and  pulse  can  be  obtained,  it  will  not  be  necessary  for  us  to  make 
extended  remarks  under  this  heading.  Medication  being  practically 
nil  in  our  cases,  both  temperature-curve  and  pulse  can  be  accepted  as 
faithfully  representing  wnat  normally  takes  place  in  an  attack  of 
this  disease.  When  ice  water  enemas  or  cold  sponge  baths  were 
used  by  the  attending  physician,  this  is  noted  on  the  chart.  It 
should  also  be  remembered  that  pur  patients  were  put  to  bed  at  the 
very  first  manifestation  of  the  disease,  and  carefully  transported  to 
the  yellow-fever  wards  on  the  very  same  beds  which  they  had  occu- 
pied in  camp.  This  probably  had  some  effect  upon  the  subsequent 
course  of  the  fever.  The  record  of  temperature  being  taken  every  3 
hours  from  the  time  of  inoculation  enables  us  to  give  the  complete 
curves  of  both  the  primary  and  secondary  febrile  paroxysm.  Our 
charts  therefore  differ  considerably  from  those  given  by  the  various 
writers  on  yellow  fever  in  that  they  round  out,  as  it  were,  the  primary 
stage  more  fully.  An  examination  of  these  charts  will  show  that 
although  the  primary  rise  of  temperature  is  tolerably  abrupt  and 
reaches  its  height  within  a  comparatively  short  time,  it  does  not 
reach  its  maximum  so  quickly  as  the  description  of  writers  would 
seem  to  indicate.  The  trihpurly  record  in  10  of  our  mosquito  inocu- 
lations shows  that  this  period  of  primary  rise  varies  from  12  to  24 
hours.  In  3  cases  it  was  12  hours;  in  2,  15  hours;  in  1,  15J  hours; 
in  1,  20J  hours;  in  1,  22  J  hours;  and  in  2,  24  hours.  The  average 
period  of  the  10  cases  was  therefore  a  fraction  over  16  hours. 

In  striking  contrast  to  these  was  the  short  period  of  the  primary 
rise  of  temperature  in  the  4  cases  produced  by  blood  injection.  In 
these  it  varied  from  2\  to  9  hours,  the  remaining  2  cases  giving  6  and 
7  hours  respectively,  the  average  for  the  4  cases  being  only  6  hours. 
In  all  of  the  12  cases  due  to  mosquito  inoculation,  the  primary  rise  of 
temperature  was  followed  by  a  distinct  remission  or  intermission, 
which  was  generally  reached  within  48  hours.  The  same  remission 
was  present  in  3  of  the  4  cases  produced  by  blood  injection.  We  are 


128 


YELLOW   FEVER. 


able  to  give  the  duration  of  the  primary  paroxysm  accurately  in  the 
10  cases  produced  at  Camp  Lazear  by  the  bites  of  mosquitos,  viz.: 


The  average  duration  of  these  10  cases  was  43  hours.  In  i 
cases  caused  by  the  injection  of  blood  tin*  length  of  the  primary 
paroxysm  was  24  hours  in  2  cases  and  36  hours  in  1  case — tin- 
being  28  hours.  We  may  therefore  say  that  not  only  the  average 
period  of  incubation,  but  also  the  primary  rise  of  temperature,  as 
well  as  the  length  of  the  first  febrile  stair*'  were  all  shorter  in  the 
cases  produced  by  blood  injection  than  in  those  due  to  the  mos- 
miito's  bite.  Of  the  12  cases  due  to  the  latter  mode  of  inoenlation 
tne  first  febrile  stage  was  followed  by  an  intermission  in  'J,  and  a 
remission  in  10  cases.  Of  those  produced  by  the  injection  of  blood, 
3  showed  a  distinct  remission  and  1  no  intervening  fall  of  temp 
ture.  The  duration  of  this  intermission  varied  from  3  to  27  hours. 
This  was. followed  by  a  second  febrile  stage  or  paroxysm  in  1 1  of  the 
12  mosquito  inoculations,  and  in  3  of  the  4  cases  due  to  the  injection 
of  blooa.  The  duration  of  this  second  febrile  paroxysm  was  from  2 
to  5  days. 

Experimental  yellow  fever  then,  as  we  saw  it  at  Camp  Lazear, 
consisted  of  a  primary  and  secondary  febrile  paroxysm,  with  an 
intervening  remission  or  intermission — more  frequently  the  former. 
The  secondary  was  much  longer  than  the  primary  febrile  stage. 

In  1  of  our  mosquito  inoculations  a  relapse  occurred  on  the  ninth 
day  of  the  disease,  and  was  characterized  also  by  -  febrile  stages 
with  an  intervening  remission.     There  were  present  head  at  In 
backache,  with  injection  of  the  eyes  and  face,  together  with  hemorr- 
hage from  the  gums,  as  had  been  observed  in  the  primary  attaek. 

The  want  of  correlation  between  temperature  and  pulse  (Fa^r 
law),  upon  which  clinicians  rely  as  an  important  diagnostic  sign, 
was  seen  as  a  rule  in  our  experimental  cases,  i.  e.,  after  the  passage 
of  the  first  febrile  stage.     In  1  case  produced  by  the  injection  of 
blood,  Facet's  law  was  not  complied  wit  h. 

The  unne. — We  have  confined  our  examination  of  the  urine  lar 
to  testing  for  the  presence  of  albumin  and  to  t  lie  ordinary  micros* 
examination  of  this  fluid.     Heat  and  nitric  acid  was  the  met  hod 
in  all  cases  for  the  detection  of  albumin,  the  specimen  having  lir-t 
been  carefully  filtered. 

Under  this  heading  we  desire  to  speak  only  concerning  tin    j 
ence  of  albumin.     AB  writers  dwell  on  the  importance  or  a  careful 
examination  of  the  urine  in  suspicious  cases  of  fever,  since  the  \ 
ence  of  albumin  in  the  urine  is  such  a  constant  sign  in  yellow  fever. 
Guiteras,  who  has  had  a  large  experience  with  this  disease,  says: 


YELLOW    FEVER. 


129 


"The  albumin  appears  in  the  urine  usually  on  the  third  or  fourth 
day  of  the  disease.  It  may  be  very  transient.  In  many  mild  cases 
the  albumin  is  present  only  in  the  urine  passed  in  the  evening  of  the 
third  or  fourth  day.  In  many  cases  it  is  only  a  trace.'7  We  may 
say  that  the  results  obtained  from  examination  of  the  urine  of  experi- 
mental yellow  fever  accords  for  the  most  part  with  the  statements 
above  quoted. 

TABLE  II. 


Case. 

Albumin  during  period  of 
incubation. 

Time  of  ap- 
pearance of 
albumin 
during  the 
attack. 

Time  of  disappearance 
of   albumin   dating 
from  appearance. 

Maximum  quantity. 

1 

Mosquito  inoculation: 

None 

Hours. 
42 

Tenth  day 

Eight-  tenths  by  volume. 

2 

None 

25 

Eleventh  day 

Three-tenths  by  volume 

3..   . 

None 

82i 

Fifteenth  day 

Two-tenths  by  volume. 

4  

None  

48 

Fifth  day  

Distinct  trace. 

5  

None 

64^ 

Fourth  day 

Light  trace. 

6 

None 

43  1 

Third  day 

Distinct  trace. 

7... 

None  

111 

Eighth  day 

Do. 

8.... 

None 

43 

Ninth  day 

One-fortieth  by  volume. 

9  

None  

42 

Twelfth  day  

One-twentieth  by  volume. 

10  

None 

75 

Eighth  day 

Distinct  trace. 

11  

None  

106 

Fifteenth  day  

One-fortieth  by  volume. 

12  

None 

None. 

One-twentieth  by  volume. 

13 

Blood  inoculation: 
None 

61 

Thirteenth  day 

Distinct  trace 

14  

None 

17 

Twelfth  day 

Do. 

15  

None  

57 

Ninth  day  

Do. 

16  

None 

18$ 

Fifteenth  day 

One-tenth  by  volume. 

1  Albumin  did  not  appear  till  36  hours  after  fever  had  subsided  and  persisted  for  five  days. 

In  our  earlier  cases  we  did  not  examine  for  albumin  until  the  onset 
of  the  attack.  In  our  last  8  cases  (those  embraced  in  this  report)  we 
examined  daily  specimens  from  the  time  of  inoculation  until  the  attack 
began,  and  thereafter  we  endeavored  to  examine  every  specimen 
passed  by  the  patient.  Table  II  gives  the  results  obtained. 

An  examination  of  the  cases  presented  in  this  table  will  show  that 
of  the  12  mosquito  inoculations  the  earliest  appearance  of  albumin 
was  at  the  beginning  of  the  second  day  in  1  case;  during  the  second 
day  in  5 ;  at  the  end  of  the  second  day  in  1 ;  during  the  third  day  in  1 ; 
during  the  fourth  day  in  2;  during  the  fifth  day  in  1;  while  in  1 — a 
well-marked  case — no  albumin  could  be  detected  till  36  hours  after 
the  temperature  had  reached  the  normal,  i.  e.,  till  the  second  day  of 
convalescence;  it  then  persisted  during  5  days.  In  all  23  specimens 
of  urine  were  examined  in  this  case  during  the  6  days  of  fever,  but 
with  an  entirely  negative  result  as  regards  the  presence  of  albumin. 
An  occasional  hyaline  or  fine  granular  cast  could  be  found  in  the 
majority  of  these  specimens.  We  submit  this  case  of  experimental 
yellow  fever  as  one  of  especial  importance  from  the  clinical  stand- 
point, since  the  absence  of  albumin  during  the  attack  would  have 
probably  led  to  an  error  in  diagnosis.  How  very  exceptional  such 
cases  may  be  we  have  no  means  of  knowing.1 

It  will  be  observed  that  the  quantity  of  albumin  present  in  this 
series  of  cases  was  very  moderate,  except  in  Cases  I  ana  II  of  Table  II. 
These  cases  were  the  only  2  of  the  16  that  were  not  placed  in  bed  from 

1  It  is  of  interest  to  note  that  this  particular  individual,  2  weeks  prior  to  successful  inoculation  and  while 
in  quarantine,  had  an  intermittent  albuniinuria  which  lasted  3  days. 

79965°— S.  Doc.  822,  61-3 9 


130  \EB. 

the  very  beginning  of  the  attack.  In  the  remaining  11.  all  of  whom 
were  kept  at  absolute  rest  during  the  whole  period  of  the  fever,  the 
amount  of  allnunin  wai  small  in  r>  and  inMirniticant  in  B.  We  are 
inclined  to  believe,  therefore,  that  both  the  course  of  the  fevc: 
well  as  the  quantity  of  albumin,  were  favorably  affected  by  the  ea  rly 
enforced  rest  of  our  patiem-. 

In  conclusion  we  desire  to  invite  attention  to  J  nintters  which 
consider  of  consideimble  importance  in  connection  \\ith  the  p.>^il>le 

importation  and  propairat  i.»n  of  yellow  fever.  Kir-t.  \\e  helie\e  that 
the  facts  herewith  presented  indicate  that  the  period  of  incuhation  of 
yellow  1.  aMonully  exceeds  the  quarantine  period  ol  :>  days, 

and  that  although  exceptional  this  must  not  bo  left  out  of  considera- 
tion. Secondly,  that  our  observations  eniphaM/.e  anew  the  impor- 
tance of  the  recognition  by  the  profe>H«>n  «,f  mild  and  very  mild  cases 
of  yellow  fever.  Guiteras  *  says:  "I  can  m>t  in-M  too  much  upon 
the  importance  of  the  diairnnMs  of  the  iirst  case  of  yellow  fever  in  a 
locality.''  He  adds:  "  Undoubtedly  the  cause  of  the  epidemic  ol  \  el- 
low  fever  is  to  be  found  in  the  introduction  into  a  community  of  cases 
that  are  not  suspected  to  be  yellow  fever."  In  the  lijjht  of  our  ii 
tigations,  we  feel  constrained  to  remark  that  the  failure  to  d. 
cases  of  mild  yellow  fever  has  been,  we  believe,  the  most  important 
factor  in  the  development  of  the  theory  of  the  propagation  of  this 
disease  by  fomites. 

>  Report  of  United  States  Marine-Hospital  Service,  Vol.  XXVII,  1897-1896,  p.  300. 


.' 


OR    JESSE  W.  LAZEAR 


CHAPTER  6. 

THE  PREVENTION  OF  YELLOW  FEVER.1 

By  WALTER  REED,  M.  D.,  Surgeon,  United  States  Army,  and  JAMES  CARROLL,  M.  D., 
Contract  Surgeon,  United  States  Army. 

The  prevention  of  yellow  fever  since  its  first  importation  into  the 
United  States  in  1693,  and  especially  during  the  latter  half  of  the 
past  century,  has  commanded,  perhaps,  more  attention  on  the  part 
of  those  who  were  concerned  with  matters  pertaining  to  the  public 
health  than  the  prevention  of  any  of  the  other  acute  infections. 
This  has  not  been  occasioned  by  the  fact  that  its  total  sickness  and 
mortality  have  exceeded  that  of  other  acute  infectious  diseases,  such 
as  typhoid  fever  or  croupous  pneumonia,  but  because  rather  of  the 
proximity  of  its  source  to  our  shores;  the  lack  of  knowledge  of  its 
specific  agent;  the  consequent  mystery  surrounding  its  origin  and 
propagation;  the  alarmingly  rapid  spread  and  course  of  this  disease, 
when  once  it  had  obtained  a  foothold,  and  the  high  mortality  with 
which  its  epidemics  have  generally  been  attended.  Although  the 
duration  of  its  presence  in  our  seaports  was  plainly  limited  by  certain 
seasonal  conditions,  yet  during  its  brief  reign  —  July  to  October  —  its 
ravages  were  such  as  to  completely  paralyze  both  the  social  and  com- 
mercial interests  of  a  given  city,  and  even  of  an  entire  section  of  our 
countrv. 

The  interval  between  1793  and  1888  is  almost  100  years,  but  upon 
the  appearance  of  yellow  fever  we  observe  no  difference  of  behavior 
on  the  part  of  the  inhabitants  of  Jackson,  Miss.,  in  1888,  from  that 
shown  by  the  citizens  of  Philadelphia  in  1793,  except  that  the  terror 
of  the  former  was  greater  and  their  flight  from  their  homes  more 
precipitate  than  in  the  case  of  the  latter. 

The  recurrence  of  succeeding  epidemics  has,  therefore,  served  to 
increase  rather  than  to  lessenthe  public  alarm.  ___  —  -!  --  -  *** 

Tt  would  li^  difficnl^  tft^Thrr,f>r]ninft  with  fl.p.r.nrfl,£yt,hp.  1o^  nf  life 
occasj^njedj^yj^  by  yellow  fever  during 

the  past  208  years.  *  We  have  endeavored  to  collect  from  the  most 
available  sources  the  mortality  caused  by  this  disease,  but  have  been 
unable  to  obtain  any  reliable  data  for  the  earlier  epidemics.  If  we 
confine  ourselves  to  the  epidemics  which  have  occurred  since  1793, 
we  find  that  there  have  not  been  less  than  100,000  deaths  from  this 
cause.  The  greatest  sufferer  has  been  the  city  of  New  Orleans,  with 
41,348  deaths,  followed  by  the  city  of  PhiladeJpnTa";  with  10.038 
(ligatfis.  The  epidemics  of  1855,  1873,  1878,  and  1879  claimed  7T759 


.  ^  ,  ,  ,  T 

victims  in  the  city  of  Memphis.  Tenn.  From  1800  to  1876,  Charleston 
lost  4,565  of  its  citizens  by  attacks  of  yellow  fever.  New  York, 
during  tHe  earlier  and  later  invasions  of  this  disease,  has  had  ,3,454 
deaths,  while  the  epidemic  of  1855  in  Norfolk^JVa.,  caused  oVer^OOO 

1  Read  at  the  29th  annual  meeting  of  the  American  Public  Health  Association,  held  in  Buffalo,  N.  Y., 
Sept.  16-21,  1901. 

131 


132  YELLOW  FEVER. 

deaths.     Durini:  our  brief  occupation  of  the  island  of  Tuba     July, 
1898-December,  1900),  with  every  precaution  brought  into 
to  ward  off  the  disease,  there  have  occurred  among  the  officers  and 
men  of  our  Army  1,575  cases  of  yellow  fever,  with  231  deal  1 

If  we  reckon  the  average  mortality  at  20  per  cent,  there  have  not 
been  less  than  500,000  cases  of  yeflow  fever  in  the  United  States 
during* the  period  fr«»m  I7«.i:i  to  I'.MIO. 

Turning  for  a  moment  to  other  conntrie-.  \\c  find  that  the  ^reai 
epidemic  of  IMIII.  in  the  province  of  Andalusia,  Spain.  <-au>ed  <'>(>. nnn 
deaths,  and  thai  '  more  deaths  attended  the  invasion  of  the 

city  of  Barcelona  by  this  disease  in  ivjl.     From  1851  to  1883,  the 
deaths  from  this  cause  in   the  city  of  Rio  de  Janeiro  \\en 
while  in  the  city  of  Habana,  between  the  years  1853  and  1900,  3.r> 
deaths  have  been  recorded  from  yellow  foyer. 

We  have  no  means  of  coinput  ing  the  damage  done  to  the  conn nenial 
interests  of  the  United  States  by  epidemics  of  yellow  fever.  At  the 
sixtli  annual  meeting  of  this  association,  held  in  Richmond.  Ya..  in 
1878,  Dr.  Samuel  Choppin.  pre-ident  of  the  State  board  «.f  health  <>f 
Louisiana,  estimated  the  actual  cost  of  the  epidemic  of  that  year  to 
the  material  resources  of  the  city  of  New  Orleans  as  $10, 7  "j 
Dr.  Benjamin  Lee,  the  present  distinguished  occupant  of  the  pi 
dential  chair,  at  the  seventeenth  annual  meeting  of  this  association, 
held  in  Brooklyn,  N.  Y.,  in  1889,  contributed  a  paper  having  the 
title,  "Do  the  Sanitary  Interests  of  the  United  States  Demand  the 
Annexation  of  Cuba?  From  this  we  quote  the  following  sent* 
4<A  single  widespread  epidemic  of  yellow  fever  wrould  cost  the  United 
States  more  in  money,  to  say  nothing  of  the  grief  and  misery  \\hich 
it  would  entail,  than  the  purchase  money  of  Cuba."  That  this 
was  no  exaggeration,  witness  the  language  of  the  petition  which  the 
chairman  of  the  committee  on  the  etiology  of  yellow  fever,  in  << in- 
junction with  other  prominent  members  or  this  association,  presented 
to  the  President  of  the  United  States  on  November  15,  1897,  and 
again,  on  November  21,  1898,  in  accordance  with  a  resolution  adopted 
at  the  meeting  of  this  association,  held  at  Ottawa.  Canada,  in  i 
In  addressing  President  M< -Kinley,  Dr.  Horlbeck  said:  It  i-  hardly 
necessary  to  call  your  attention  to  the  serious  result^  of  the  recent 
epidemic  of  yellow  fever  in  the  States  of  Louisiana,  Mi->i  — ippi,  and 
Alabama,  but  we  may  be  permitted  to  mention  the  fact  that  the 
great  epidemic  of  1878  resulted  in  the  loss  of  nearly  16,000  li\e>.  and 
that  it  nas  been  estimated  that  the  total  loss  to  the  country  resulting 
from  this  epidemic  was  not  less  than  $100,000,000." 

The  importance  of  the  study  of  the  causative  factors  entering  into 
the  propagation  of  a  disease  so  capable  of  (prickly  de>t roving  the  lives 
of  the  citizens  and  wrecking  the  commercial  intere>t>  of  the  < -itie> 
of  the  United  States  could  hardly  be  overestimated.  Did  time 
permit,  we  would  be  glad  to  refer  to  the  numerous  and  valuable 
contributions  made  to  this  subject  by  the  members  of  the  American 
Health  Association.  We  can  only  mention  the  establishment  of  the 
National  Board  of  Health  and  the  appointment  of  the  Habana  Yellow 
Fever  Commission  of  1879  as  two  of  the  most  important  outconn 
the  persistent  efforts  of  this  association,  following  "the  deeply  tragical 
events  of  the  summer  of  1878."  The  exhaustive  reports  made  by 
chailli'-  in  l^'i,  iind  by  Sternberg  in  1890^  must  always  stand  as 
monuments  to  the  earnest  spirit  of  investigation  with  which  the  work 
pursued. 


YELLOW   FEVER.  133 

Notwithstanding  the  importance  of  the  work  and  the  efforts  put 
forth  by  students  in  this  and  other  countries,  we  believe  that  we  are 
safe  in  saying  that  no  results  had  been  obtained  which  would  enable 
us  to  combat  successfully  this  disease  when  once  imported  into  our 
larger  centers  of  population,  and  no  means  found  to  keep  it  out  of 
our  ports  except  such  as  would  place  very  heavy  burdens  upon  com- 
merce. This  inability  to  control  the  disease  grew  not  only  out  of  our 
ignorance  as  to  the  way  or  ways  in  which  yellow  fever  was  propagated, 
but  also  out  of  certain  false  opinions  which  we  had  formed  as  to  the 
mode  of  its  spread.  The  doctrine  of  the  spread  of  yellow  fever  by 
fomites  and  by  filth  had  taken  such  hold  on  the  professional  mind 
as  completely  to  overshadow  all  other  views,  and  to  direct  into  false 
channels  the  work  of  those  who  were  engaged  in  the  investigation  of 
this  disease.  The  efforts  to  isolate  or  to  discover  the  specific  agent  of 
yellow  fever,  if  successful,  would  possibly  have  greatly  simplified  the 
problem ;  in  the  absence  of  such  discovery,  the  first  step  in  our  knowl- 
edge of  how  to  prevent  this  disease  could  only  be  found,  we  think, 
along  another  line,  viz,  that  of  its  propagation  from  the  sick  to  the 
well.  This  step  we  endeavored  to  take  in  connection  with  our  col- 
leagues, Dr.  Agramonte  and  the  late  Dr.  J.  W.  Lazear  of  the  United 
States  Army,  during  our  recent  investigations  into  the  causation  and 
spread  of  yellow  fever  at  Quemados,  Cuba. 

The  results  of  our  earlier  work  relative  to  the  etiology  and  propa- 
gation of  this  disease  we  had  the  pleasure  of  presenting  to  this  asso- 
ciation at  its  last  meeting,  held  in  Indianapolis,  Ind.1  You  will  recall 
that  one  of  the  conclusions  which  we  then  submitted  was  as  follows: 
uThe  mosquito  serves  as  the  intermediate  host  for  the  parasite  of 
yellow  fever."  In  the  same  article,  we  briefly  indicated  the  reasons 
which  influenced  us  in  pursuing  this  line  of  investigation,  and  it  is, 
therefore,  unnecessary  here  to  repeat  them. 

Continuing  our  studies,  especially  as  regards  the  means  by  which 
yellow  fever  is  spread  from  individual  to  individual,  and  as  to  the 
manner  in  which  houses  become  infected,  we  were  able,  under  strict 
rules  of  isolation  and  quarantine,  to  bring  about  an  attack  of  yellow 
fever  in  10  nonimmune  individuals  (and  always  within  the  period  of 
incubation  of  this  disease)  out  of  a  total  of  13  (76.84  per  cent)  whom 
we  attempted  to  infect  by  means  of  the  bites  of  mosquitoes — Stegomyia 
fasciata — that  had  previously  been  fed  with  the  blood  of  yellow-fever 
patients  during  the  first,  second,  and  third  days  of  their  attacks. 
These  results  were  reported  in  part  to  the  Pan-American  Congress 
held  in  Habana  during  February  of  this  year,2  and  in  part  to  the 
Association  of  American  Physicians  at  its  last  meeting,  held  in  the  city 
of  Washington.3 

It  will  be  seen  that  we  were  able  to  establish  in  the  most  conclusive 
manner  that  the  mosquito  does  serve  as  the  intermediate  host  for 
the  parasite  of  yellow  fever.  At  this  same  experimental  sanitary 
station  we  were  also  able  to  demonstrate  that  an  attack  of  yellow 
fever  can  not  be  induced  by  the  most  intimate  and  prolonged  contact 
with  the  clothing  and  bedding  of  yellow-fever  patients,  even  though 
these  articles  had  been  previously  thoroughly  and  purposely  soiled 
with  the  excreta  of  such  patients.  In  other  words,  we  were  able  to 

1  "The  EtMogy  of  Yellow  Fever— A  Preliminary  Note. "    Philadelphia  Medical  Journal,  Oct.  27, 1900. 
;<The  Etiology  of  Yellow  Fever— An  Additional  Note."    Journal  American  Medical  Association, 


Feb.  16',  1901. 
8  "Experimental  Yellow  Fever. "    American  Medicine,  July,  1901. 


134  YKI.I.«'\\ 

prove  that  the  garments  \\orn,  and  the  bedding  used,  by  yellow-fever 
patients  were  no  more  concerned  in  propagating  this  disease  than  the 
clothing  and  bedding  of  patients  suffering  from  malarial  fever  are 
erned  in  the  spread  of  the  latter  malady.  The  doctrine  of  the 
spread  of  yellow  fever  by  foiuites  having,  at  the  iir>t  touch  of  actual 
experiment  on  human  beings,  burst  like  a  bubble,  we  may  hereafter 
cast  it  aside,  with  other  exploded  beliefs,  to  the  very  great  simplifi- 
cation of  the  problem  how  to  prevent  yellow  fever.  Indeed,  in  our 
opinion,  the  time  has  now  arrived  when  the  latter  problem  max  be 
reduce. 1  to  measures  which  shall  prexent  the  pmpairat  imi  of  this  dis- 
ease by  mosquitoes.  Although  this  specific  a-jvnt  of  \ello\\  fever  has 

not,  as  yet,  teen  discovered,  this  must  remain  largely  a  mailer  of 
scientific  interest,  and  does  not  in  the  least  lessen  the  efforts  \\hieh 
we,  as  sanitarians,  are  now  able  for  the  first  time  to  bring  into  ;t. -tion 
for  the  prevention  of  the  spread  of  this  disea.-e.  since  in  dealing  with 
the  mosquito  we  are  dealing  with  the  intermediate  host  which  <  ; 
the  specific  a  :ent-from  the  sick  to  the  \\ell. 

In  considering,  then,  in  abroad  way,  the  prevent  ion  of  yell- 
the  natural  order  would  be  to  give  our  attention,  first,  to  mea> 
which  will  prevent  the  importation  of  this  disease  from 
places  into  the  seaports  of  the  United  States;  and  secondly,  to  meas- 
ures which  will  most  effectually  prevent  the  spread  of  this  di>< 
provided  it  should  <jain  a  lodgment  in  one  of  the  cities  of  this  con 

With  your  permission,  however,  we  will  reverse  the  order  of  . 
sideration  above  suggested,  and  will  later  refer  in  the  briefest  manner 
to  the  prevention  of  the  importation  of  yellow  fever  into  the  t'i 
States  Irom  foreign  ports,  as  this  part  of  "the  subject  will  be  prese: 
by  the  health  officer  of  the  port  of  New  York,  who,  from  lo> 
rience,  will  be  able  to  deal  more  intelligently  than  we  with  this  part 
of  the  problem. 

Since  the  mosquito,  especially  that  species  of  stegomyia  which  has 
recently  been  designated  by  Theobald  as  Stegomyia  fasciuta  (formerly 
knowrn  to  entomologists  as  Culexfasciatus  Fab.),  has  become  so  prom- 
inent a  factor  in  the  spread  of  yellow  fever,  it  becoi 
consider  this  insect  from  the  point  of  view  of  its  identification;  its 
habitat;  its  breeding  places;  the  length  of  its  generation;  its  I. 
of  feeding;    the  influence  of  temperature  upon  both  its  propagation 
and   stinging;  the  interval    after   contamination    b 
becomes  capable  of  propagating  the  disease;  the  length  of  time  during 
which  it  remains  dangerous;    the  measures  that  should  be  used  n«»t 
only  to  protect  the  sick  against  the  bites  of  these  insects;  but  aUo  to 
prevent  the  latter  from  infect  ing  the,  healthy  individual:   and.  finally. 
a  consideration  of  the  several  agents  which   may  be  successfully 

employed    both    to    prevent    the    breeding  of   moMiuitnes    MS    \\ell    a's 

ted  toward  their  de-t  •  net  ion  in  the  adult  si 

Aside  from  the  standpoint  of  scientific  inter,  ;iinly   a 

matter  of  hygienic  importance,  in  taking  \i\>  the  <pie-ii«m  of  how  to 
prevent  the  spread  of  yellow  fever,  when  imported  into  the,  Tniicd 
States,  that  trie  health  authorities  of  our  several  <<  .-md. 

indeed,  of  some  of  our  inland   i  honld   bo  able  to  determine 

whether  the  only  species  of  mosquito,  which,  up  to  the  pre>ent  < 
has  been  shown  capable  of  conveying  yellow  fever,  is  or  is  Dot 
in  these  cities.     If  it  should  hereafter  be  pi<.\en  that  only  spcci. 
the  genus  stegomyia  are  capable  of  net  in-/  a#  intermedi..  for 


YELLOW    FEVER.  135 

the  specific  agent  of  yellow  fever,  as  appears  to  have  been  demon- 
strated for  the  geuus  anopheles  in  the  spread  of  malaria,  the  presence 
or  absence  of  the  former  genus  will  definitely  determine  whether 
yellow  fever  will  or  will  not  spread  in  a  given  locality.  The  presence 
or  absence  of  mosquitoes  that  can  propagate  the  disease  is  the  only 
intelligible  explanation  of  what  has  heretofore  been  considered  an 
inexplicable  problem,  viz,  the  capability  of  this  disease  to  propagate 
itself  in  certain  localities,  while  in  other  places  it  could  be  introduced 
with  perfect  impunity  to  the  public  health.  In  other  words,  our 
present  knowledge  of  this  question  solves,  at  last,  the  problem  of  the 
portability  or  nonportability  o'f  yellow  fever. 

Description  of  mosquito. — The  identification  of  stegomyia  fasciata, 
Theobald,  should  not  be  difficult.  This  mosquito,  when  examined 
closely  with  the  naked  eye  and  especially  with  a  pocket  lens,  is  a 
rather  striking-looking  and  handsome  insect.  (Fig.  1.)  Its  most 
conspicuous  markings  are  the  broad  semilunar  silvery  stripe,  which 
is  seen  on  the  lateral  surface  of  the  thorax,  and  the  white  stripes  at 
the  bases  of  the  tarsal  joints.  These  may  be  readily  distinguished 
with  the  naked  eye.  The  bands  on  the  hind  legs  are  especially  well 
marked,  and  occasionally  the  entire  fifth  hind  tarsal  joint  is  seen  to 
be  of  a  pure  silvery  white.  The  four  stripes  of  silvery  scales  which 
are  seen  on  the  posterior  surface  of  the  thorax  serve  to  distinguish 
this  species  from  all  other  mosquitoes,  except  stegomyia  signifer, 
Coquillet,  in  which,  however,  as  we  have  been  informed  by  Mr.  L.  O. 
Howard,  the  curved  thoracic  band  is  very  narrow  and  of  a  somewhat 
different  shape.  Examined  with  a  hand  lens,  the  four  stripes  are 
seen  to  consist  of  two  lateral,  distinct  silver  lines — the  continuation 
of  the  semilunar,  broad  stripes — and  two  fine,  white  lines  situated 
between  these,  and  which  require  that  the  insect  shall  be  held  in  the 
proper  light,  in  order  that  these  delicate  threads  may  be  distinctly 
seen.  The  lateral  surface  of  the  thorax  is  also  marked  by  several 
silvery  dots  and  the  abdomen  by  distinct  white  stripes.  This  de- 
scription applies  to  both  sexes.  In  the  female,  the  palpi  are  short, 
as  in  the  genus  culex.  The  proboscis  is  of  a  dark  blackish-brown 
color  and  is  destitute  of  a  whitish  band  near  the  middle.  In  the 
male  (fig.  2),  one  of  the  front  tarsal  claws  bears  a  tooth  on  the  under 
side,  while  the  other  claw  is  destitute  of  such  marking.  In  the 
female,  both  front  tarsal  claws  bear  a  distinct  tooth  near  the  base 
of  the  under  side  of  each. 

Habitat. — We  have  found  this  mosquito  in  all  of  the  principal  cities 
of  Cuba,  and  have  received  specimens  from  a  number  of  the  smaller 
towns  on  this  island.  According  to  Howard  1  it  has  been  found  at 
Kingston,  Jamaica,  on  the  Isle  of  Pines,  and  at  Bluefields,  Nicaragua. 
He  also  reports  that  Theobald  has  received  specimens  of  this  insect 
from  Italy,  Greece,  Spain,  Portugal,  Gibraltar,  and  Malta.  ,  In  the 
United  States,  Howard  reports  its  presence  a  t  New  Orleans,  Natchi- 
tochez,  and  Napoleonville,  La., ;  in  eastern  Texas ;  Hot  Springs,  Ark. ; 
Pelham,  Ga. ;  and  from  Virginia  Beach,  near  Norfolk,  Va.  To  this 
we  can  add  Augusta,  Ga.,  from  which  city  we  have  recently  received 
specimens  of  stegomyia  fasciata  through  the  courtesy  of  Dr.  T.  O. 
Oertel  of  that  city.  Dr.  Durham,  of  the  English  commission  for  the 
study  of  yellow  fever,  kindly  showed  us  specimens  of  this  insect  which 

1  "Mosquitoes,"  etc.,  by  L.  O.  Howard,  New  Yorti,  1901. 


he  had  collected  at  Para,  Hra/.il.  and  a;  \arious  places  alon<:  the 
Amazon  River.  It  will  be  seen,  then-tore,  that  stegomyiafasciata  has 
a  \\ide  distribution  in  the  \\armcr  countries  of  the  globe,  and  espe- 
cially at  low  altitudes.  A  more  exact  kno\\ledire  of  the  distribution 
of  this  mosquito  in  the  United  States  is,  \\e  think,  a  matter  of  con- 
siderable practical  importance. 

Breeding  places. — In  our  search  for  the  larvae  of  this  insect  we  have 
found   them   in   the   following  place.-:  I    rain-\\ater  barn-U  : 

in  sagging  pit  ters  containing  rain  \\  ater;   ('.\ )  in  tin  cans  that  had  been 
used  for  re  i  no  v  ing  excreta  ami  which  still  contained  a  small  amount  of 
fecal  matter:   i  Din  cesspools;  (5    in  tin  can-  placed  about  table  le-- 
io  prevent  the  inroads  of  red  ants;  (6)  in  the  collection  of  \\-.\\- 
the  base  of  the  leaves  of  the  agave  americana;  (7)  in  one  end 


Fio.  1.— Stegomyla  fasciata;  female,    a,  Front  tarsal  claw. 

horse  trough  that  was  in  daily  use.  It  follows  that  ste^omvia.  like 
culex,  will  oreed  in  any  collection  of  still  water,  rain  or  hydrant,  and 
that  the  presence  of  fecal  matter  does  not  seem  objection  able.  Indeed, 
we  have  been  in  the  habit  of  adding  a  \«ry  small  quantity  of  the  latter 
to  our  breeding  jars,  as  it  has  seemed  to  hasten  the  development 
of  the  larvae.  In  water,  however,  which  contains  much  su-pended 
soil — muddy  water — the  larvae,  in  our  experience,  do  not  llouri>h. 
but  die  off  rather  rapidly. 

Deposition  of  eggs. — The  insect,  lays  her  e.^s  durinir  the  niirht,  and, 
unlike  culex.  \\hirh  deposits  its  eggs  in  boat  like  masses,  stegomyia 
extrudes  her  e^^  <>n  tho  surface  of  the  water  in  pairs,  in  p-oiij 

thn r    more,    or    singly:   in    llii-    respecl     re-em blin.ir    anoph- 

(Fig.  3.)     Exceptionally,  the  eggs  are  deposited  in  a   rather  close- 


YELLOW   FEVER.  137 

lying  mass.  (Fig.  4.)  The  whole  batch  is  laid  in  one  night,  or 
extending  over  two  or  three  nights.  The  number  of  eggs  deposited 
varies  from  about  20  to  about  75 — rarely  a  larger  number.  Sixteen 
careful  counts  gave  an  average  of  47  eggs.  At  the  same  time  that  the 
female  deposits  her  eggs,  she  frequently,  but  not  always,  discharges  a 
fluid  which  forms  a  very  thin  film  over  the  surface  of  the  water,  which 
possibly  assists  in  floating  the  eggs.  The  latter  are  of  a  jet-black 
color  and,  to  the  naked  eye,  cylindrical  in  shape,  one  end  of  the  egg 
being  rounded  and  blunt,  while  the  other  is  slightly  pointed,  the 
whole  resembling  closely  a  Conchita  cigar.  They  measure  about 
0.65  mm.  in  length  by  0.17  mm.  in  width  at  the  broadest  part.  Under 
a  low  power,  the  surface  of  the  eggs  is  seen  to  be  marked  by  tolerably 
regular  six-sided  plates,  each  of  which  is  further  marked  in  the  center 


FIG.  2.— Stegomyia  fasciata;  male,    a,  Front  tarsal  claw. 

by  a  little  round  elevation,  which  gives  to  the  surface  of  the  egg  a 
decidedly  roughened  appearance.  (Fig.  5.)  Under  this  low  ampli- 
fication it  is  also  seen  that,  while  one  side  of  the  egg  is  somewhat  con- 
vex, the  other  is  flat  or  slightly  concave  and  that  a  cross  section  of 
the  egg  would  present  the  appearance  of  a  triangle  instead  of  that  of 
a  cylinder.  This  flattening  of  the  surface  of  the  egg  does  not  appear 
to  extend  quite  to  the  ends,  which  are  round  in  shape.  Although 
floating  perfectly  if  left  undisturbed,  any  agitation  of  the  water, 
especially  of  a  rough  character,  is  apt  to  cause  some  or  a  majority 
of  the  eggs  to  sink.  If  by  slight  pressure  the  egg  is  pushed  beneath 
the  surface  of  the  water  it  at  once  sinks  and  does  not  rise  again. 
This  sinking  of  the  eggs  does  not  interfere  with  their  subsequent 
hatching,  as  in  our  experience  submerged  eggs  furnish  about  as  many 
larvae  as  those  which  are  left  floating  on  the  surface. 


138 


\  ER. 


The  resistance  of  stegomyia's  eggs  to  external  influences  is  worthy 
of  note.  Drying  seems  to  be  but Tittle  injurious  to  their  subsequent 
fertility.  We  have  found  that  eggs  dried  on  lilter  paper,  and  kent 
for  periods  of  from  10  to  *»n  day-,  will  promptly 
hatch  \\hen  again  submerged  in  water.  Pried 
eggs  brought  with  us  from  llabana.  in  Feb- 
ruary, were  easily  hatched  (luring  the  month 
of  May  in  Washington,  furnishing  about  (>0 
per  cent  of  the  usual  number  of  larva*  hatched 
from  fresh  eLTgs.  Free/ing  doefl  r.ot  destroy 
the  fertility  of  the  eggs;  although  free/.ing  with 
a  mixture  Of  salt  and  iee  for  :in  minnto  bafl 
:d  times  seemed  to  prevent  -ul»equent 
hatcliing;  on  one  occasion  a  bat  eh  of  1  .~>5  eggs, 
freslilv  deposited,  which  were  fro/en  at  a 
ture  of  —  17°  C.,  for  one  hour,  then  thawed  out  at  room  tempera- 
ture and  placed  in  the  incubator  at  35°  C.,  began  to  hatch  on  the 
sixth  day.  the  majority  furnishing  active  larvae  on  the  eighth  day. 
In  another  observation,  freshly  deposited  eggs, 
frozen  at  — 17°  C.  for  half  an  hour  on  two  succes- 
sive days,  began  to  hatch  on  the  third  day  as  usual 
at  incubator  temperature.  The  resistance  of  ste- 
gomyia's  eggs  to  drying  for  a  period  of  three 
months  would  appear  to  demonstrate  that  this 


10.  3.— Steromyla    fasclata. 
B»tch  of  flfiy-iwo  eggs  asde- 
!-v     :»    toffi     f, 

UjMtefed 


FIG.  4.— Stegomyia  fascl- 
ata.   Forty -eight  eggs 
deposited    In    a 
lying  mass.    Enlarged. 


appear 

genus  of  mosquito  could  survive  the  winter  in 
Habana  without  the  presence  of  hibernating 
females.  Doubtless  the  genus  is  preserved  in  botn 
ways.  It  is  probable  that  the  same  could  occur  in 
our  extreme  southern  latitudes. 

Length  of  generation. — The  impregnated  female, 
having  obtained  a  meal  of  blood,  proceeds  to  de- 
posit her  eggs,  in  captivity,  after  an  interval  vary- 
ing in  our  experience  from  2  to  30  days — as  a  rule,  the  eggs  are  laid 
within  7  days;  sometimes  a  second  or  third  meal  of  blood  is  taken 
before  any  eggs  are  laid.  Eggs  placed  .under  favorable  conditions  of 

warmth — i.  e.,  summer  or  incu- 
bator temperature — begin  to 
hatch,  as  a  rule,  on  the  third 
day,  the  period  extending  to 
about  1  week.  The  larval 
requires  7  or  8  days,  and  the 
pupal  stage  about  2  days.  The 
period  for  the  generation  may 
oe  stated,  therefore,  as  follows: 
Incubation. Mday>:  larval  stage, 
7  days;  pupal,  'u  day-:  total. 
12  days.  .As  the  .  'in  to 

hatch  before  the  expiration  of 
the  third  day,  we  generally  ob- 
tain a  few  mosquitoes  on  the 
eleventh  day.  The  shortest  period  of  development  observed  by  us  dur- 
ing summer  weather  in  Cuba  was  incubation.  *J  days;  larval  stage,  (i 
days;  pupal,  36  hour*.;  making  the  total  length  of  this  generation  \\\ 
days.  TnU  short  period  we  believe  to  be  quite,  exceptional.  Tim 


Fio.  5.— Stegomyia    fasciata.    Newly  deposited 
X  60.    a,  Empty  shell  from  which  larva  hasesoa 


YELLOW   FEVER. 


139 


FIG.  6.— Stegomyia  fasci- 
ata.  Full-grown  larva 
enlarged. 


first  fully  developed  insects  begin  to  emerge  on  the  eleventh  or  twelfth 
day,  and  the  whole  number  have  reached  maturity  by  the  fifteenth 
or  eighteenth  day  after  deposition  of  the  eggs.  The  young  larvae,  in 
emerging,  rupture  the  shell  at  a  point  about  one-fifth  the  length  of 
the  egg  from  the  larger  end.  This  cap-like  end  can  be  frequently 
seen  turned  back  and  still  adhering  to  the  rest  of  the  shell.  (Fig.  5.) 
The  larva  and  pupa  of  stegomyia  (figs.  6  and  7)  resemble  fairly 
closely  those  of  culex,  and  the  larvae  maintain  the  same  relative 
position  to  the  surface  of  the  water;  i.  e.,  while  in 
the  act  of  breathing  they  assume  a  vertical  posi- 
tion, with  the  head  directed  downward. 

Influence  of  temperature  on  propagation. — We 
have  just  seen  that  at  summer  temperatures  the 
time  required  for  a  complete  generation  of  this 
insect  is  from  11  to  18  days.  We  may  say  that 
at  an  average  temperature  of  75°  F.,  or  over, 
stegomyia  multiplies  abundantly.  Exposure  to  a 
cooler  temperature,  even  for  a  short  time  daily, 
much  retards  the  development  of  this  mosquito. 
Thus,  a  batch  of  51  eggs  kept  at  35°  C.,  but  which 
were  placed  in  a  cool  chamber. at  20°  C.  for  two 
hours  daily  during  the  whole  process  of  develop- 
ment, although  furnishing  a  few  larvae  at  the  end 
of  the  third  day,  were  not  all  hatched  until  the 
eleventh  day.  The  first  pupae  appeared  on  the 
fourteenth  day  and  the  first  mosquito  on  the 
nineteenth  day;  the  whole  process  being  completed  in  27  days,  instead 
of  the  usual  15  to  18  days.  The  loss  of  insects  was  about  50  per  cent. 
Eggs  kept  at  a  temperature  of  20°  C.  (68°  F.)  do  not  hatch,  in  our 
experience.  Newly  hatched  larvae  kept  at  this  temperature  develop 
very  slowly  and  require  about  20  days  to  reach  the  pupal  stage.  Mos- 
quitoes developed  under  such  conditions  are  feeble,  and  but  few 
arrive  at  maturity.  Young  larvae  kept  at  10°  C.  (50°  F.)  have  failed 
to  reach  the  pupal  stage,  although  some  growth  takes  place.  In  one 
experiment  more  than  50  per  cent  were  dead  at  the 
end  of  two  weeks,  and  none  survived  the  thirty-sec- 
ond day.  Half-grown  larvae  and  pupae  exposed  to  a 
temperature  of  20°  C.,  and  even  as  low  as  10°  C.,  con- 
tinue to  develop  slowly,  but  the  few  insects  which 
escape  drowning  have,  as  a  rule,  been  of  feeble 
strength  and  have  refused  to  bite.  Although  the 
reduction  of  the  temperature  to  the  freezing  point, 
or  below,  would  not  necessarily  destroy  the  vitality 
of  the  eggs  of  this  genus  of  mosquito,  it  should  be 
remembered  that  a  reduction  of  temperature  to  68°  F., 
or  below,  for  even  a  few  hours  of  the  24  will  much 
retard  the  development  of  the  generation.  At  a  temperature  less  than 
68°  F.  the  eggs  of  this  insect  nave  ceased  to  hatch. 

Influence  of  temperature  on  biting. — While  the  nonimpregnated 
female  does  not  appear  to  bite,  the  impregnated  female  is  generally 
ready  to  bite  on  the  second  or  third  day  of  her  existence;  they  very 
rarely  suck  blood  on  the  first  day.  This  species  of  mosquito,  when 
not  deprived  of  its  liberty,  although  occasionally  biting  during  the 
morning  hours,  has,  in  our  experience,  been  especially  active  from 
the  hour  of  4  p.  m.  till  midnight.  In  captivity,  the  hungry  impreg- 


FIG.  7.— Stegomyia 
fasciata.  Pupa,  en- 
larged. 


140  Y1-1LLOW   FEVEB. 

nated  female  will  bite  at  any  hour  of  the  day  or  night.  The  meal  of 
blood  appears  to  have  been  thoroughly  digested  on  the  third  day. 
when  the  bisects,  if  applied  to  the  surface  of  the  skin,  can  l>e  again 
readily  induced  to  feed.  When  freed  in  a  room,  the  female  docs  not 
appear  to  bite  a  second  time  till  about  five,  or  even  seven,  days  have 
elapsed. 

As  regards  the  effect  of  temperature  in  the  stinging  of  S/M/« 
fasciata,  the  results  of  a  number  of  observations  made  by  u>  >how 
Miuito  will  bite  at  teni|)eral  ures  of  62°  F.  and  al>o\c.      At 
temperatures  helow  this  point,  we  have  not,  as  yet, succeeded  in  in- 
ducing even  very  hungry  females  to  suck  blood.     W.  herefore, 
say  that  observations  thus   far  made  appear  to  show  that  *s 

myia/OA.  iiile  not  breeding   at   temperatures  below  (>S      F.,  will 

still  bite  at  a  temperature  as  low  as  62°  F.,  but  probably  not  at  lo\\  er 
temperatures. 

If  this  insect  is  concerned  in  the  propagation  of  yellow  foyer,  it  is 
now  unite  apparent  why  an  epidemic  of  this  disease  >h<>uld  fall  ti»  a 
low  ef)h  in  the  city  of  New  Orleans  during  the  month  of  November, 
with  a  mean  temperature  of  61.8°  F.,  and  practically  cease  in  Decem- 
ber, with  a  mean  temperature  of  55.3°  F.  A  careful  study  of  the 
charts  herewith  submitted  (figs.  8  and  9),  showing  the  monthly  mean 
temperatures  of  the  cities  of  llabana  and  New  Orleans  and  Ilahana 
and  Kio  de  Janeiro  together  \\ith  the  relative  monthly  mortality  from 
yellow  fever  in  these  cities,  will  prove  of  interest,  \\e  think,  as  show- 
ing better  than  laboratory  observations  the  general  effect  of  teni| 
ture  upon  the  breeding  and  biting  of  Stegomyiafasciata.  In  the  light 
of  recent  researches,  we  can  now  understand  that  while  yellow  I 
can,  and  does,  prevail  during  the  entire  year  in  Ilahana  and  Hi 
Janeiro — although  at  a  comparatively  low  ebb  during  the  winter 
months — it  can  not  propagate  itself  in  New  Orleans  from  December 
to  May. 

Interval  after  contamination  before  the  mosquito  becomes  dangerous.— 
In  our  experimental  work  on  human  beings,  we  have  n  <led 

hi  inducing  an  attack  of  yellow  fever  by  the  bites  of  mosquitoes  which 
had  been  kept  less  than  12  days  after  contamination.  The  same 
bisects  which  failed  to  convey  the  disease  on  the  eleventh  < lay  were 
capable  of  so  doing  on  the  seventeenth  day  after  infection.  Th  is  i  n  t  <•  r- 
val  of  about  12  days,  which  appears  necessary  for  the  development 
of  the  parasite  within  the  mosquito,  plus  the  period  of  incubation, 
agrees  with  the  time  that  has  been  ooserved  to  elai>>e  between  the 
introduction  of  an  infecting  case  into  a  locality  and  the  occurrence  of 
the  first  secondary  case,  viz,  two  to  three  weeks. 

After  the  mosquito  has  once  become  dangerous,  how  long  it  remains 
capable  of  conveying  the  disease,  although  important.  ha>  not   been 
rmined.     We  have  reported  cases  of  \cllo\v  iVver  caused  by  the 
bites  of  stegomyia  at  interval^  varying  from  \'l  to  f>7  da\s  after  con- 
tamination.   Herethedangerousintervalwas4.~M|.i\  >,but  a>«»ncoi  thc-c 

ts  lived  until  the  seven ty-first  day  after  biting  a  yell. 
patient,  the  dangerous  interval  would  here  be  prolonged  to59d 
little  over  8  weeks.     In  our  experience,  the.  mlccird  in-cd  appe.-s 
live  about  as  long  as  the  noninfected  mosquito,  so  thai  the  answer  to  thk 
que-tion  would  depend  upon  the  length  of  life  of  the  mosquito.      This 
we  do  not  know.     While  in  captivity,  the  majority  of  moMjiiito. 


YELLOW   FEVER.  141 

not  survive,  with  the  best  of  care,  more  than  about  five  weeks,  and 
many  die  within  half  of  this  tune;  we  are  ignorant  as  to  the  length  of 
time  during  which  they  may  live  when  under  natural  conditions. 
Certainly,  during  summer  weather  this  will  depend  largely  on  the 
opportunity  which  the  mosquito  has  of  obtaining  access  to  water. 

Measures  to  prevent  the  spread  of  the  disease  when  imported. — A  case 
of  yellow  fever  having  been  imported  into  one  of  our  seaport  cities, 
we  are  now  prepared  to  discuss  the  measures  that  should  be  taken 
to  prevent  its  spread.  The  problem  resolves  itself  into  the  simple 
one  of  excluding  mosquitoes  from  access  to  the  sick  individual  and 
of  destroying  those  insects  that  have  already  become  infected.  We 
can  leave  out  of  consideration  any  danger  from  wearing  apparel  or 
baggage,  which,  in  our  opinion,  may  be  dismissed  as  harmless. 

The  fear  that  has  been  entertained  that  infected  insects  may  be 
imported  in  boxes  or  trunks  we  believe  to  be  absolutely  groundless, 
and  this  for  the  simple  reason,  as  shown  by  numerous  observations 
made  by  us,  that  mosquitoes,  when  deprived  of  water,  die  within  a 
few  days.  Even  if  allowed  to  fill  themselves  with  blood  immediately 
before  the  experiment  is  begun,  and  then  deprived  of  water,  practi- 
cally all  are  dead  by  the  expiration  of  the  fifth  or  commencement  of 
the  sixth  day.  We  may  say  that  of  a  large  number  of  insects  tried 
in  this  way  only  one  female  has  survived  until  the  sixth  day,  and 
then  in  a  feeble  condition.  Males  and  females  which  have  been  living 
on  sugar  and  water,  or  fed  two  days  before  on  blood,  if  deprived  of 
water  and  food,  begin  to  die  after  24  hours,  and  all  are  dead  on  the 
fourth  morning.  Free  access  to  water,  therefore,  is  necessary  for  the 
existence  of  this  mosquito. 

Add  to  the  deprivation  of  water  the  chances  of  injury  to  so  frail 
an  insect  packed  in  with  articles  of  clothing,  etc.,  and  we  see  that 
infected  mosquitoes  can  not  be  imported  alive  in  baggage  that  has 
been  five  days  en  route. 

As  the  first  special  measure  of  prevention,  then,  we  should  give 
our  prompt  attention  to  the  protection  of  the  sick  individual  against 
the  bites  of  mosquitoes.  This  can  best  be  accomplished  by  thorough 
screening,  without  delay,  of  the  windows  and  doors  of  the  room 
occupied  by  the  patient  and  with  as  little  disturbance  as  possible,  so 
that  any  insects  already  present  in  the  room  may  be  prevented  from 
escaping.  As  it  will  not  be  feasible  to  make  use  of  any  of  the 
destructive  agents  against  mosquitoes  already  within  the  patient's 
room  until  recovery,  every  precaution  should  be  used  to  see  that  the 
insects  do  not  escape  in  opening  and  closing  the  door.  Screens  at 
windows  should  not,  for  this  reason,  be  movable.  As  it  is  possible 
that  mosquitoes  that  have  already  bitten  the  sick  individual  may 
have  escaped  into  other  apartments  of  the  house,  these  should  be 
closed  tightly  and  subjected  either  to  sulphur  or  to  formaldehyde 
disinfection  or  to  the  fumes  of  burning  pyrethrum.  According  to 
Dr.  Gorgas,  the  efficient  health  officer  of  Habana,  preference  is  given 
to  pyrethrum  powder,  burned  in  the  proportion  of  1  pound  to  1,000 
cubic  feet  of  air  space.1  He,  however,  adds : 

As  the  pyrethrum  powder,  even  in  this  large  quantity,  does  not  certainly  kill  all 
mosquitoes,  the  room  is  opened  at  the  end  of  three  hours  and  the  mosquitoes  on  the 
floor  swept  up  and  burned. 

i  Medical  Record,  New  York,  vol.  60,  No.  10,  Sept.  7, 1901. 


142 


Y  Ml.  LOW     FKVKR. 


We  have  mentioned  above,  in  the  order  of  their  eiririenry,  the 
agents  which  are  most  destructive  to  stegomyia.     According  to  our 


observations,  an  exposure  for  one  and  a  half  hours  t<>  sulphur  fumi- 
gation, in  a  well-closed  room,  in  the  proportion  of  1  pound  to  1,000 


YELLOW    FEVER.  143 

cubic  feet  of  air  space,  will  suffice  effectually  to  destroy  all  mosquitoes. 
Formaldehyde  gas  is  not  quite  so  efficient.  With  Trenner's  formal- 
dehyde generator,  charged  with  formalin,  900  c.  c.;  glycerin,  9  c.  c.; 
methyl  alcohol,  360  c.  c.,  which  we  have  found  quite  reliable  for  the 
destruction  of  bacteria,  an  exposure  of  not  less  than  three  and  pref- 
erably four  hours  is  required  in  order  to  kill  these  insects  in  a  tight 
room  having  2,800  cubic  feet  capacity.  Pyrethrum  powder,  if 
burned  in  the  proportion  of  4  ounces  to  1,000  cubic  feet  ol  air  space, 
will  stupefy  all  mosquitoes  at  the  expiration  of  one  hour,  so  that 
they  will  fall  to  the  floor  in  a  helpless  condition.  If  used,  however, 
the  precaution  above  recommended  by  Dr.  Gorgas  should  be  strictly 
followed — that  is,  the  room  should  be  opened  at  the  end  of  three 
hours  and  all  insects  carefully  swept  up  and  burned.  The  practice 
of  destroying  all  mosquitoes  in  adjoining  houses,  as  carried  out  in 
the  city  of  Habana  with  such  excellent  results,  we  consider  of  the 
greatest  importance,  since  only  in  this  way  can  we  hope  to  destroy 
infected  mosquitoes,  and  thus  preVent  the  occurrence  of  secondary 
cases.  In  other  words,  relying  upon  the  well-known  slow  progress  of 
the  spread  of  yellow  fever,  we  seek  to  catch  and  destroy  all  mosqui- 
toes within  a  given  radius  of  the  first  case.  If  secondary  cases  should 
occur,  the  same  hygienic  measures  should  be  rigorously  enforced 
along  the  lines  above  indicated.  UpOn  the  completion  of  the  case, 
the  room  occupied  by  the  patient  should  be  disinfected,  and  in  a 
matter  where  so  much  is  at  stake  we  believe  that  sulphur  should  be 
given  the  preference  as  a  disinfectant.  In  case  of  death,  the  body 
should  be  carefully  screened  against  mosquitoes,  as  stegomyia  will 
bite  the  dead  body  and  might  in  this  way-acquire  the  parasite. 

We  have  said  nothing  about  the  protection  of  nonimmune  individ- 
uals who  enter  the  patient's  room  or  housd*,  since,  if  the  case  under 
consideration  is  the  infecting  case,  no  danger  is  incurred.  As  the 
duration  of  the  attack  is  short,  generally  less  than  10  days,  the  pa- 
tient's room  will  have  been  disinfected  and  the  infected  mosquitoes 
destroyed  before  they  have  become  susceptible  of  conveying  the  dis- 
ease to  others.  We  desire  to  emphasize  the  fact  that  the  interval 
elapsing  between  the  infection  of  this  mosquito  by  biting  a  case  of 
yellow  fever  and  the  time  when  it  has  become  capable  of  conveying 
the  disease,  viz,  about  12  days,  is  of  the  utmost  importance  in  our 
efforts  toward  stamping  out  yellow  fever  at  its  very  commencement, 
since  it  furnishes  a  nondangerous  interval  during  which  all  infected 
insects  should  be  easily  destroyed.  It  thus  makes  the  control  of 
yellow  fever  hereafter  a  simpler  and  more  certain  matter  than  the 
suppression  of  an  outbreak  of  any  of  the  other  acute  infectious 
diseases.  If  nonimmunes  entering  an  infected  house  desire  protec- 
tion against  the  bites  of  stegomyia,  this  may  be  obtained  by  rubbing 
all  exposed  surfaces  of  the  body,  including  the  ankle  surfaces,  with 
spirits  of  camphor,  oil  of  pennyroyal,  or  a  5  per  cent  menthol  oint- 
ment. The  protective  effect  of  these  substances  is,  however,  only 
temporary. 

What  we  have  already  said  concerning  the  breeding  places  of 
Stegomyia  fasciata  should  sufficiently  indicate  the  general  hygienic 
measures  that  should  be  taken  in  order  to  prevent  the  spread  of  yellow 
fever.  These  should  consist  in  enforcing  such  measures  as  will  effec- 
tually destroy  the  breeding  places  of  this  very  domestic  mosquito. 


144  YELLOW  FEVEB. 

The  methods  adopted  by  the  chief  sanitary  officer  of  llabana.  durini: 
the  present  year,  may  be  taken  as  a  model  by  our  sanitary  officials.1 
It  should  not  be  .'ii  that  a  well-drained  and  well-sewered  city. 

with  a  pure  v  ;Tlv  an^  ('l(ian  Mreets  lias  no  pr.itcction  against 

the  spread  of  yellow  fever.  pr»\  ided  rain-water  barrels  and  other  col- 
ons of  water  are  present ,  in  which  stegomyiamay  breed.     In  one 
of  the  forts,  on  the  outskirts  of  llabana,  which  was  other\\i-e  in  an 
ilent  san  .lni..n.  \\«>  fnnnd  t housands  of  Stegomyiafasciata 

breeding  in  tin  oana  placed  about  the  legs  of  a  table  in  an  oil 
kitchen.     Our  con.  ept  ion  of  yellow  fever,  therefore,  as  a  "filth"  dis- 
ease must  be  abandoned,  and  our  attention   turned   to  yellow  fever 
as  a  mosquito-borne  disease.     In  illustration  of  \\hat  may  be  accom- 

1*111  •  i  i  .ill..  ..  i          i         r 


plished  by  sanitation  based  on  the  latter  method  of  propagation,  we 
present  herewith  a  chart  (fig.  10)  showing  the  actual  monthly 
tality  from  yellow  fever  in  llabana,  for  the  period  from  isso  to  i 


and  also  for  the  years  1900  and  1901.     Comparing  the  mortality  from 
ix'.w,  which  was  the  most  favorable  ye.  -How 

:•  that  Habana  had  experienced  in  L.M)  years,  with    1!«H.  during 
which  sanitation,  based  on  the  demonstration  that  yellow  fev< 
propagated  by  the  mosquito,  lias  been  enforced.  \\e  find  a  reduction 
in  mortality  of  83.3  per  cent  in  favor  of  the  present  epidemic 

.  1  to  Aug.  31);  or  if  we  compare  the  mortality  f«»r  the  epidemic 
year  1900  with  the  present  year  we  observe  a  still  greater  reduction 
in  favor  of  the  latter,  viz,  411  per  cent. 

The  sanitary  regulations  put  into  force  February  15,   H»ni.   by 
Dr.  Gorgas,  resulted  in  freeing  Habana  from  yellow  fever  within  :; 
months,  so  that  for  a  period  of  54  days — May  7  to  July  1— no 
occurred.    On  the  latter  date,  the  disease  was  brought  into  Ilai 
from  Santiago  de  las  Vegas,  and,  according  to  Gorgas,  has  l>een  intro- 
duced into  the  city  at  least  a  dozen  times  from  this  and  ot  her 
In  spite  of  these  new  sources  of  infection,  July  has  only  furnished 
four  cases,  with  one  death,  and  August  eight  cases,  with  two  deaths. 
If  such  admirable  results,  under  new  methods  of  sanitation,  have  been 
obtained  in  this  hotbed  of  yellow  fever,  we  can  not  believe  that  the 
intelligent  and  efficient  boards  of  health  of  pur  cities  will  again  nermit 
this  disease  to  assume  an  epidemic  form  in  any  city  of  the  United 
States. 

Measures  directed  against  the  importation  of  yellow  fever  into  the 
United  States. — Under  the  admirable  system  of  inspection  and  rep' 
as  carried  out  by  the  Marine  Hospital  Service,  the  appearaix  e  of  yel- 
low fever  at  any  foreign  port  is  promptly  reported  for  the  informat  ion 
of  the  health  authorities  of  our  several  Atlantic  ports.  We  may, 
therefore,  divide  foreign  ports  within  the  so-called  epidemic 
into  (a)  infected,  and  (o)  noninfected  ports.  Heretofore,  no  distinc- 
tion has  been  made  by  the  health  officers  of  our  southern  ports  as 
regards  quarantine  regulations  from  April  1  to  November  1,  between 
infected  and  noninfected  places.  All  ports  within  the  epidemic  zone 
of  yellow  fever  were  considered  as  being  infected  places,  and  hence  pas- 
sengers and  vessels  were  subjected  to  quarantine  and  to  disinfection 
of  both  baggage  and  cargoes. 

With  our  present  knowledge  of  the  way  in  which  yellow  fever  is 
propagated,  we  believe  that  in  the  treatment  of  passengers,  as  well 

*  Medical  Record,  New  York,  vol.  60,  Sept.  7. 1001. 


YELLOW   FEVEK. 


145 


as  of  cargoes,  a  sharp  distinction  should  be  made,  first,  between 
infected  and  noninfected  ports;  and,  secondly,  in  the  case  of  vessels 
sailing  from  infected  ports,  between  those  that  have  received  their 
cargoes  and  passengers  in  midstream  and  those  that  have  loaded  at 
the  wharf. 


fleatfa 


months, 


anuary: 


JUMA. 


October. 


eeemder. 


a 


Ztegrees.  fl&ner&teff. 


We  believe  that  no  quarantine  restrictions  should  be  placed  upon 

either  passengers  or  cargo  from  noninfected  ports.     In  the  case  of  a 

vessel  loading  in  midstream  at  an  infected  port  by  means  of  lighters, 

we  believe  that  she  can  only  receive  infection  in  one  way,  i.  e.,  by 

79965°— S.  Doc.  822,  61-3 10 


146  YELLOW    FEVER. 

passengers  who  have  been  exposed  to  yellow  fever  on  shore,  and  who. 
coming  aboard,  may  thereafter  be  seized  with  the  disease.  The  po«.<i- 
hility  of  infected  mosquitoes  reaching  the  vessel,  either  by  flight  or 
by  means  of  lighters,  may  be  considered  as  highly  improbable. 

Vessels, loaded  under  the  foregoing  circumstances  (i.e., by  lighters 
in  midstream),  and  arriving  at  our  ports  without  yellow  fever  devel- 
oped en  route  should  have  their  DOniinmune  nas-enircrs  quarantined 
for  live  days,  counting  t  he  time  consumed  by  the  voyage  as  pa  it  of  the 
quarantine  period,  and  should  be  allowed  to  discharge  their  car 
without  delay.  If  the  disease  has  developed  en  route  amonir  ciw\ 
or  passe:  he  siek  should  he  promptly  removed;  the  forecastle 

taterooms,  as  the  case  may  he.  thoroughly  disinfected  with  sul- 
phur or  formaldehyde  gas,  and  the  vessel  allowed  to  proceed  to  her 
wharf. 

On  the  other  hand,  if  the  vessel  has  received  her  cargo  at  the  wharf 
of  an  infected  port,  there  is  a  possibility  that  she  may  have  recen  ed 
infection  in  three  ways:  Kirst,  either  by  contaminated  mosquitoe< 
that  have  bitten  a  case  of  yellow  fever  in  the  immediate  vicinity  on 
shore;  secondly,  by  mosquitoes  that  have  become  infected  from"  bit- 
ing a  yellow-fever  patient  present  on  another  vessel  loading  at  the 
same,  or  at  an  adjacent,  wharf;  or,  thirdly,  by  some  individual  who 
has  acquired  the  infection  on  shore  and  afterwards  taken  pass  at 
the  vessel. 

In  our  opinion,  however,  the  chances  of  infection  of  a  vessel  by 
contaminated  mosquitoes  coming  aboard  from  a  house  or  ship  in 
close  proximity  are  very  slight;  although  such  a  possibility  must  be 
admitted,  and  the  further  possibility  that  recently  infected  m<  >s<  \\ ; 
may  have  sought  refuge  on  the  vessel  during  the  night  preceding  her 
day  of  departure.     It  is  also  possible  that  a  case  of  mud  and  1 
undetected  yellow  fever  may  occur  on  board,  and  be  the  sour* 
the  infection  of  mosquitoes  already  present  in  the  vessel. 

Under  these  circumstances,  if  a  sufficient  number  of  days  have  not 
elapsed  between  her  port  of  departure  and  port  of  arrival  in  the  United 
States,  i.  e.,  16  to  21  days,  to  demonstrate  the  presence  of  inf« 
mosquitoes  by  the  occurrence  of  a  case  or  cases  of  yellow  fever  en 
route,  we  know  of  no  way  of  absolutely  excluding  the  possibility  of 
importation  of  the  disease  by  such  a  vessel  than  by  the  detention  of 
all  nonimmune  passengers  for  such  number  of  days  a.s  will  show  their 
freedom  from  infection,  and  by  careful  disinfection  of  crew's  and 
passengers'  quarters. 

If  more  than  20  days  have  elapsed  during  the  voyage,  without  the 
occurrence  of  yellow  fever,  we  see  no  good  reason  why  either  pa 
gers  or  vessel  should  be  detained. 

We  have  said  nothing  about  the  disinfection  of  the  vessel' 
for  the  reason  that  we  do  not  consider  this  to  be  necessary.  The  only 
possible  excuse  for  subject  in<:  the  cargo  to  disinfection  would  be  the 
lear  of  the  presence  of  infected  mosquitoes  in  the  vessel's  hold,  pro- 
vided she  had  loaded  at  the  wharf  of  an  infected  port.  In  this 
instance,  if  the  voyage  has  consumed  five  or  more  days,  all  mosqui- 
toes contained  in  the  hold  will  have  died:  for,  as  we  have  already 
pointed  out,  Stegomyia  fasciata  lives  only  a  few  days  if  deprived  of 
water.  We  can  not  too  strongly  insist  that  the  danger  of  importation 
of  yellow  fever  into  the  United  States  lies,  not  in  cargo  or  personal 


YELLOW  FEVER. 


147 


8 


Mynter  cf  deaths 

ft  8 


January 


•Jtyust- 


October  - 


148  YELLOW    l-T.YKK. 

baggage,  but  in  the  individual  sick  with  that  disease.  With  our 
present  knowledge  of  its  propagation,  personal  baggage  should  no 
longer  be  subjected  to  disinfection,  and,  with  our  in.  !>ility  to 

prevent  its  spread  l>y  m  application,  instances  should 

be  few  ami  exceptional  when  a  vessel  coming  from  a  yellow-fever  port 
should  be  delay cd  lonuvr  than  will  he  necessary  to  remove  her  n«>n- 
iinmune  passenL  t  yet  completed  their  period  of  live 

days  since  leaving  the  port  of  departure. 

The  chief  duty  of  (|iiarantine  officers  hereafter  will  coiiM-t   in  the 
i  of  mild  or  very  mild  cases  of  vellow  fever.     J 

[mental  yellow  fever  produced  by  thebiteof  flffcyomyw 
fasc'uitn.  we  nave,  elsewhere.1  jx'inted  out  that  4,  or  .'>.">   \ 

mild  «>r  verv  mild  in  character,  and  have  indicated  the  dillicnlty 
of  making  a  positive  diagnosis  in  such  cases. 

In  discu^>iuLT  the  period  of  incubation  of  experimental  yellow  f« 
we  have  shown  that  in  i«;.i;  per  cent  of  our  cases  the  period  of  incu- 
bation exceeded  the  usual  quarantine  period  of  live  days.      1:     «  add 
Carter's  cases  to  those  observed  by  ourselves,  we  find  that  of  iM 
the  period  of  incubation  exceeded  five  days  in  3,  or  L2.5  per  cent. 

We  can  thus  readily  see  what  great  danger  heretofore  lay  in  the 
passage  through  quarantine  of  just  such  mild  cases,  or  of  those  ha 
an  incubation  stage  of  more  than  five  days. 

While  the  exclusion  of  such  cases  is  of  thegreate-t  importance,  we 
doubt  whether,  with  our  improved  knowledge  of  how  to  prevent  the 
spread  of  yellow  fever,  it  would  be  advisable  to  place  a  greater  hunlen 
upon  ships'  passengers  by  extending  the  quarantine  period  to  more 
than  five  days.  It  appears  to  us  rather  that  in  view  of  the  trou hie- 
some  delays  to  which  passengers  and  vessels  from  yellow-fever  : 
have  been  subjected  in  the  past,  the  time  has  now  arrived  when. 
standing  upon  more  solid  ground,  we  will  be  justified  in  seeking  in 
every  way  to  lessen  as  much  as  possible  the  restrictions  placed  by 
present  quarantine  regulations  upon  the  ship's  cargo,  while  we  add 
nothing  to  those  of  the  passenger. 

To  this  end  a  most  important  part  will  have  been  accomplished  if 
we  can  persuade  the  sanitary  authorities  of  our  sister  republic,  M.  \i« ... 
and  of  the  Central  and  South  American  States,  to  join  us  in  the  adop- 
tion of  more  enlightened  methods  for  the  suppression  of  this  widely 
prevalent  epidemic. 

« '•  Experimental  Yellow  Fever."    Transactions  of  the  Association  of  American   Physicians, 


Vol. 


CHAPTER  7. 

THE  ETIOLOGY  OF  YELLOW  FEVER— A  SUPPLEMENTAL  NOTE.1 

By  WALTER  REED,  M.  D.,  Surgeon,  United  States  Army,  and  JAMES  CARROLL,  M.  D., 
Contract  Surgeon,  United  States  Army,  of  Washington,  D.  C. 

Informer  contributions  to  this  subject,  we  have  shown  by  observa- 
tions made  on  human  beings  that  yellow  fever  may  be  produced  in 
the  nonimmune  in  dividual  either  by  the  bite  of  the  mosquito  (1)  (genus 
Stegomyia)  that  has  previously  been  permitted  to  fill  itself  with  the 
blood  of  a  patient  suffering  with  yellow  fever,  during  the  first  three 
days  of  the  attack,  or  by  the  subcutaneous  injection  of  a  small  quan- 
tity of  blood  (2)  (0.5  to  2  c.  c.)  drawn  from  the  general  circulation 
of  such  a  patient  during  the  active  stage  of  this  disease.  For  further 
particulars  regarding  these  observations  the  reader  is  referred  to  the 
original  papers. 

Although  these  experiments  have  demonstrated  that  the  specific 
agent  of  yellow  fever  is  present  in  the  blood,  we  may  say  that  the 
prolonged  microscopic  search  which  has  been  made  by  other  investi- 
gators, as  well  as  by  ourselves,  both  with  fresh  and  stained  prepara- 
tions of  blood,  taken  at  various  stages  of  this  disease  and  during  early 
convalescence,  has  proved  thus  far  entirely  negative.  We  may 
add  that  the  efforts  which  we  have  made  with  reasonable  hope  of 
reward,  both  in  the  bodies  of  infected  mosquitoes,  dissected  in  the 
fresh  state,  as  well  as  by  serial  sections  of  the  hardened  insect,  have 
likewise  given  no  results  which  we  consider  worthy  of  record  at  the 
present  time.  Leaving  out  of  consideration,  therefore,  for  the  time 
being,  the  further  microscopic  search  for  the  specific  agent  in  the 
blood  of  the  sick  and  in  the  bodies  of  infected  mosquitoes,  we  desire 
to  call  attention  to  some  additional  observations  bearing  on  the 
etiology  of  the  disease,  which  one  of  us  (Carroll)  has  recently  made 
at  Las  Animas  Hospital,  Habana,  Cuba,  and  at  Columbia  Barracks, 
near  Quemados,  Cuba. 

We  here  desire  to  express  our  sincere  thanks  to  Dr.  William  H.  Welch, 
of  the  Johns  Hopkins  University,  who,  during  the  past  summer, 
kindly  called  our  attention  to  the  important  observations  which  have 
been  carried  out  in  late  years  by  Loeffier  and  Frosch  relative  to  the 
etiology  and  prevention  of  foot-and-mouth  disease  in  cattle.  In  the 
course  of  their  investigations  concerning  a  reliable  method  of  immu- 
nization in  this  disease,  the  authors  had  occasion  to  dilute  and  after- 
wards to  pass  several  times  through  a  porcelain  filter,  lymph  which 
had  been  collected  from  the  blebs  present  in  the  mouth  and  on  the 
feet  of  cattle  sick  with  foot-and-mouth  disease  (4). 

These  observers,  having  already  ascertained  that  immunity  could 
be  conferred  upon  cattle  by  the  subcutaneous  or  intravenous  injec- 
tion of  one -fortieth  to  one-fiftieth  c.  c.  of  pure  lymph  previously 

»  Read  before  the  third  annual  meeting  of  the  Society  of  American  Bacteriologists,  Chicago,  111.,  Dec.  31, 
1901,  and  Jan.  1, 1902. 


150  YELLOW   FEVER. 

mixed  with  1  c.  c.  of  the  defibfinated  blood  of  an  animal  that  had 
recently  recovered  from  the  disease,  desired  to  find  out  whether  the 
injection  into  calves  of  given  quantities  of  this  filtered  ami  hacteria- 
free  lymph  would  not.  also,  enable  them  to  confer  immunity  of. 
perhaps,  a  higher  degree  upon  cattle. 

The  roults  were  quite  surprising,  since  it  was  sho\\  n  that  eaKes 
\\hich  had  received  one-tenth  to  one-fortieth  c.  C.  of  the  diluted  and 
filtered  lymph  «;<  1  foot-and-mouth  di>ea>e  ju-t  as  prompt  lv 

MCalves'that  had  heen  injeeteil  \\  it  h  corresponding  quant  it  ies  of  t  he 
unfiltered  lymph. 

According  to  Loefflcr  and  Froseh.  there  were  two  po—ihlr  e\plana- 
tions  of  this  remarkable  result ;  either  that  the  filtered  lymph  held  in 
solution  an  extraordinary  active  t«»\in.  or  that  the  specific  a.ircnt  of 
the  disease  was  so  minute  as  to  pass  through  the  p«.i-,  iihcr 

which  prevents  the  passage  of  the  smalle-i  Un«>\\  n  bacteria. 

The  authors  accept  the  latter  explanation,  since  they  were  able, 
in  later  experiments  *,  1  .  by  means  of  the  filtered  lymph. to  convey  the 

iae  through  a  series  of  MX   animaU.  the  last  of  which 
just  as  promj)tly  after  the  injection  of  the  filtered   lymph  a>  the  iii>t 
of  the  series. 

Having,  therefore .  conclusively  determined  that  the  ini<  aisrn 

of  foot-and-mouth  disease  of  cattle  is  so  extremely  minute  a 
readilv  through  a  porcelain  filter,   it    was  natural  that    L(»: 
Froseh  should  have  put  forward  tbft 
specific  agent  of  some  of  the  acute  infecti 
animals,  such  as  smallpox,  scarlet  fever,  m 
mi*rht  also  belong  to  this  <_rn>up  of  ultramicroscopi 

It  was  for  the  purpose  of  ascertaining  whether  observation  con- 
ducted along  the  same  lines  as  those  ahove  mentioned   niiixht  throw 
additional  light  upon  the  etiology  of  yellow  fever  that  the  folio-, 
experiments  were  undertaken. 

Of  course  it  will  be  thoroughly  appreciated  that  in  experimentation 
on  human  beings,  aside  from  the  ^rave  sense  -nsihiliu  .  ai 

times  well-ni^h  in>uj)nortahle,  which  the  conscientious  observer  nni-i 
al\\ays  fed.  even   with  the  full  c«»n>cnt   of  the  Mihjects  to  he  ex]>eri- 
mented  uj>on,  there  must  be  added  another  factor,  vi/,  the  dilliculty 
of  lindinj;  willing  and  suitable  nonimmune  individual 
tation  just  at  the  proper  and  urgent  moment.     It  so  happened  that 
on  the  day  of  Dr.  Carroll's  arrival  at  Habana,  Au«ru>t  11.  l(.«n  ,  th« 
patient  or  the  series  of  seven  cases  of  yellow  fever  which  Dr.  (  hn 
had  j)roduce<l   hy  hites  of  infected  mosquitoes,  was  taken  sick.      The 
fatal  termination  of  three  of  these  cases  produced  a  somewhat  panicky 
feelini:  toward  experimental  yellow  fever  among  the  nonimmmi< 
Habana,  which  feeling  was  Intensified  by  the  sensational  and  di-t- 
statements  in  one  of  the  local  Spanish  papers.      It    was,   ihei-efore, 
extremely   difficult — in   fact,   practically   impossible — to   obtain    for 
inoculation  purposes  person-  who  could  with  reasonable  certainly  l.e 
regarded  as  nonimmunes. 

Further,  as  it  was  not  practical >le  to  \\ithdraw  hlood  from  any  . 
of  yellow  fever  under  treatment    in  the  city  of  Habana.   it    heeame 
necessary  to  produce  cases  by  means  of  the  hites  of  infected  i 
rpiitoes—  Stegom i/ia fasciata— accepting  such  subjects  as  \\erc  willing 
to  submit  to  this  mode  of  inoculation.      In  all  MX  individu.-: 
posedly  nonimniurH's,  were  bitten  l.y  mosquitoes,  of  whom  four  gave 
a  negative  and  two  a  positive  result. 


YELLOW   FEVER.  151 

The  following  are  the  negative  cases : 

August  14,  1901 —S.  V.,  Spaniard,  resident  of  Habana  for  a  few  months,  was  bitten 
by  two  insects  that  had  been  applied  to  a  yellow  fever  patient  34  days  previously 
Result  negative,  although  the  bites  of  two  mosquitoes  from  this  same  lot  had  already 
infected  an  individual,  who  later  died  of  yellow  fever. 

September  5,  1901.— J.  T.,  American,  was  bitten  by  nine  insects  that  had  been  ap- 
plied to  a  mild  case  of  yellow  fever  on  the  second  day  of  the  attack,  23  days  before. 
He  was  again  bitten  30  days  later  by  four  mosquitoes  that  had  been  applied  to  a  mod- 
erately severe  case  of  experimental  yellow  fever  11  days  before.  The  result  of  both 
inoculations  were  negative.  This  man  had  resided  one  year  in  Central  America,  and 
we  were  afterwards  informed  that  he  had  confessed  to  a  previous  attack  of  the  disease. 

September  11,  1901.— A.  P.,  Spaniard,  was  bitten  by  three  insects  which  53  days 
previously  had  bitten  patient  with  a  typical  case,  on  the  third  day  of  the  attack. 
These  were  among  a  lot  of  mosquitoes  that  had  already  infected  three  individuals, 
two  of  whom  died  of  yellow  fever.  The  result  was  negative.  Five  weeks  later  he 
received  a  subcutaneous  injection  of  about  one-fourth  c.  c.  of  blood  drawn  from  a 
patient  with  a  mild  case  of  yellow  fever,  on  the  second  day  of  illness.  Result  negative. 
The  previous  history  of  this  man  was  not  satisfactory,  as  he  had  recently  returned  from 
a  residence  in  Mexico. 

September  9,  1901. — A.  V.,  Spaniard,  was  bitten  by  three  mosquitoes  that  had  been 
applied  to  a  mild  case  of  yellow  fever  on  the  second  day  of  the  attack,  27  days  before. 
Three  weeks  later  he  was  again  bitten  by  one  mosquito  49  days  after  it  had  been  ap- 
plied to  a  fatal  case  of  yellow  fever,  on  the  third  day  of  the  attack.  The  result  of 
both  inoculations  was  negative. 

We  give  brief  sketches  of  the  two  positive  cases: 

Case  I. — P.  R.  C.,  a  Spaniard,  had  served  in  the  Spanish  army  in  the  Philippines. 
He  arrived  in  Habana  from  Spain  about  August  30. 

On  September  16,  1901,  he  was  bitten  at  4  p.  m.  by  4  mosquitoes  that  had  previ- 
ously fed  upon  cases  of  yellow  fever  as  follows:  One  had  bitten  a  patient  having  a 
fatal  case,  on  the  third  day  of  the  disease,  53  days  before,  and  3  haa  bitten  a  patient 
having  a  fatal  case,  on  the  second  day  of  illness,  34  days  previously.  His  attack 
began  at  4.30  p.  m.,  September  19,  after  an  incubation  period  of  72^  hours.  At  the 
onset  he  experienced  a  slight  chill  with  rigors  and  loss  of  appetite.  Later  in  the 
evening  he  complained  of  slight  frontal  headache  and  pains  in  the  lumbar  region. 
On  the  following  day  the  headache  and  backache  were  more  severe.  At  10  a.  m.  he 
vomited  about  6  drams  of  slightly  greenish  fluid  containing  mucus.  On  the  second 
day  of  the  attack  the  gums  were  swollen,  pale,  and  spongy,  and  there  .was  soreness 
upon  deep  pressure  over  the  epigastric  and  hypogastric  regions;  the  face  was  flushed 
and  the  eyeballs  were  slightly  yellow.  September  24,  fifth  day,  he  was  well  jaun- 
diced, epigastric  and  abdominal  soreness  were  pronounced,  and  there  was  nausea 
with  eructations.  At  this  time  an  unfavorable  prognosis  was  given  by  two  physi- 
cians of  large  experience  in  yellow  fever.  Happily,  with  the  decline  of  temperature 
on  the  sixth  day,  the  symptoms  were  much  ameliorated  and  the  patient  made  an  un- 
interrupted recovery.  Albumin  appeared  in  the  urine  on  the  third  day  and  persisted 
for  17  days.  The  microscope  showed  the  presence  of  bile-stained  epithelial  and 
granular  casts  on  the  third  and  subsequent  days. 

Early  on  the  second  day  blood  was  drawn  from  the  median-basilic  vein  with  all 
precaution  and  10  drops  were  immediately  added  to  each  of  four  flasks  containing 
200  c.  c.  of  sterile  nutritive  bouillon.  The  flasks  were  kept  under  observation  in  the 
incubator  and  at  room  temperature  for  14  days  without  the  development  of  any  growth. 
At  the  end  of  that  time  each  flask  was  agitated  and  an  agar  slant  was  freely  inoculated 
with  fibrin  and  fluid  from  its  contents.  These  cultures  remained  sterile  16  days 
later  after  being  kept  four  days  in  the  incubator  and  12  at  room  temperature. 

On  the  second  day,  blood  was  drawn  for  the  purpose  of  obtaining  serum  for  filtration, 
but  owing  to  an  accident  to  the  vacuum  pump  the  experiment  had  to  be  abandoned. 

Specimens  of  the  fresh  blood  were  examined  for  malarial  parasites,  with  negative 
results,  on.  the  second  and  fourth  days  of  the  attack.  (Chart  I.) 

Case  II.— J.  M.  A.,  Spaniard,  recently  landed  at  Havana,  was  bitten  at  4  p.  m. 
October  9,  by  8  mosquitoes  that  had  been  applied  to  a  severe  case  of  yellow  fever 
(Case  I)  on  the  second  day  of  the  disease,  18  days  previously.  The  attack  which  fol- 
lowed was  mild.  According  to  his  own  account,  he  went  to  bed  on  the  evening  of 
the  12th  feeling  in  perfect  health.  He  awakened  about  midnight  with  frontal 
headache,  but  had  no  chill.  October  13,  7  a.  m.,  temperature  was  102.2°  F.,  pulse 
92;  complained  of  pain  in  the  head  and  back;  later  in  the  day  there  was  marked 
photophobia,  pain  in  the  region  of  the  kidneys,  and  slight  pains  in  the  lower  extremi- 


152 


VEB. 


i  •••••••  ••••»-"••••••••••••••••••••••••  •••••rj< 

•••••••• =-•••••••••••••••••••••••••!••••••• i j> 

<••=•••••••••••••••••••••••••••••••••          mvm\ 


YELLOW   FEVER.  153 

ties.  The  eyes  were  injected  moderately  and  the  gums  slightly  so.  On  the  follow- 
ing day,  October  14,  the  frontal  headache  was  more  severe,  there  was  considerable 
soreness  on  pressure  over  the  stomach  and  abdomen,  and  he  complained  of  sharp 
lumbar  pain.  An  examination  of  the  fresh  blood  proved  negative  for  malarial  para- 
sites. At  4  p.  m.  blood  was  drawn  from  a  vein  at  the  bend  of  the  elbow  and  10  drops 
were  inoculated  into  each  of  2  flasks  containing  200  c.  c.  of  sterile  bouillon.  One 
flask  remained  sterile,  the  other  developed  a  growth  which  proved  to  be  a  white 
staphylococcus. 

October  15  the  gums  were  pale,  swollen  and  spongy,  their  margins  distinctly  red- 
dened, and  blood  could  be  easily  pressed  out  from  beneath  the  lower  gums. 

October  16  there  was  free  oozing  of  blood  from  the  gums  and  margin  of  the  tongue. 
The  case  pursued  a  mild  course,  the  temperature  falling  to  normal  at  9  p.  m.  of  the 
fourth  day.  A  trace  of  albumin  was  present  in  the  urine  passed  on  the  morning  of  that 
day,  and  for  a  few  days  following  hyalin  and  granular  casts  were  found.  The  patient 
made  a  speedy  recovery.  (Chart  II.) 

On  October  15, 11.30  a.  m.,  at  the  beginning  of  the  third  day  of  illness,  the  tempera- 
ture was  101°  F.;  65  c.  c.  of  blood  were  drawn,  with  antiseptic  precautions,  from  a  vein 
at  the  bend  of  the  elbow.  This  was  placed  in  a  sterile  test  tube  and  set  aside  in  the 
refrigerator.  At  6  a.  m.,  5^  hours  later,  19  c.  c.  of  a  slightly  bloodstained  serum  were 
pipetted  off  into  another  sterile  tube.  After  the  addition  of  an  equal  quantity  of 
sterilized  distilled  water  the  diluted  serum  was  slowly  filtered  through  a  new  Berke- 
feld  laboratory  filter  that  had  been  subjected  to  previous  sterilization  in  an  Arnold's 
sterilizer.  In  this  way  35  c.  c.  of  a  slightly  bloodstained  filtrate  were  obtained,  a  part 
of  which  was  subsequently  used  for  the  inoculation  of  Cases  VII,  VII,  and  IX  of  this 
report. 

The  original  level  of  the  blood  having  been  marked  upon  the  tube  into  which  it 
was  drawn,  a  sufficient  quantity  of  sterilized  distilled  water  was  then  added  to  replace 
the  19  c.  c.  of  serum  that  had  been  pipetted  off  and  to  make  up  the  original  volume  of 
blood.  The  whole,  consisting  of  clot,  remaining  serum,  and  distilled  water,  was 
poured  into  a  sterile  vessel  and  whipped  up  with  a  sterilized  egg  beater.  The  mix- 
ture, which  approximately  represented  the  partially  defibrinated  blood,  was  then 
divided  into  two  parts,  one  of  which  was  reserved  for  the  inoculation  of  a  control  sub- 
ject (Case  III),  while  the  other  part  was  placed  in  a  double  water  bath  previously 
heated,  and  exposed  to  a  temperature  of  55°  C.  for  10  minutes.  It  was  then  remo  ved 
and  immediately  cooled  in  ice  water.  This  cooled  material  was  subsequently  used  for 
the  injection  of  Cases  IV,  V,  and  VI. 

It  will  thus  be  seen  that  we  have  at  our  disposal,  for  purposes  of 
inoculation,  three  kinds  of  materials,  derived  from  the  blood  in  Case 
II,  viz:  (a)  The  unheated  and  partially  defibrinated  blood;  (&)  the 
partially  defibrinated  blood  which  had  be.en  heated  to  a  temperature 
of  55°  C.  for  10  minutes,  and  (c)  the  diluted  blood  serum  which  had 
been  filtered  through  a  Berkefeld  filter.  Each  of  these  materials 
was  used  for  the  inoculation  of  one  or  more  nonimmune  individuals 
with  the  results  that  follow  herewith. 

(a)   THE    UNHEATED   AND  PARTIALLY   DEFIBRINATED   BLOOD. 

Case  IIL—M..  G.  M.,  Spaniard,  arrived  at  Habana  October  4,  1901.  At  4  p.  m. 
October  15  he  was  given  a  subcutaneous  injection  of  0.75  c.  c.  of  the  unheated  and 
partially  defibrinated  blood  obtained  from  Case  II,  15 J  hours  previously,  which  had 
been  kept  5£  hours  in  the  refrigerator  and  10  hours  at  room  temperature.  The  earliest 
symptom,  frontal  headache,  was  complained  of  at  6  p.  m.,  October  20,  or  at  the  expi- 
ration of  5  days  and  2  hours  after  inoculation.  Temperature  100.6°  F.,  pulse  80.  At 
3  p.  m.  of  the  same  day  the  temperature  was  98.4°  F.,  pulse  80.  At  that  time  the 
patient  did  not  complain  of  any  discomfort  and  there  was  nothing  to  indicate  that  he 
was  about  to  be  taken  sick.  October  21,  5  p.  m.,  nearly  24  hours  From  the  onset,  there 
was  flushing  of  the  face,  injection  of  the  eyes  and  gums,  and  moderately  severe  head- 
*ache;  pain  in  the  back,  and  tenderness  on  pressure  in  the  epigastric  region  made  the 
picture  complete.  On  the  third  day  the  face  was  deeply  flushed,  eyes  congested 
and  distinctly  yellow.  There  was  slight  oozing  of  blood  from  the  gums.  The  urine 
passed  at  7.30  p.  m.  contained  a  distinct  trace  of  albumin.  The  case  was  seen  by  the 
Habana  Board  of  Yellow  Fever  Experts  and  the  diagnosis  confirmed.  The  patient 
passed  through  a  mild  but  typical  attack,  the  temperature  touching  normal  on  the 
fifth  day.  (Chart  III.) 


154 


This  case,  therefore,  serves  as  a  'vontrol"  for  the  observations 
\\hich  are  to  follo\\ .  >inee  it  demons rates  that  the  Mood  drawn  frum 
the  general  circulation  of  case  II,  at  the  hednnini:  of  the  thinl  day. 
contained  the  specific  agent  of  yellow  fever,  and,  in  this  resnect .  con- 
firms the  observations  which  have  heretofore  been  reported  b\  u 


!••*••••-•••••••! 

'•••••••••••••••I 

(•••••••••••••••I 


••••••••••••••••I 


(b)    THE   PARTIALLY   DEFIBRINATED   BLOOD   HEATED   FOR    10    MINUTES 

AT   55°   C. 

Cote  IV.— A.  C.,  Spaniard,  iioniininune,  arrived  at  Habana,  Octobor  <;.  1!»(> 
4.35  p.  m.,  October  15.  he  was  given  eubcutaneously  1.5  c.  c.  of  th<-  partially  <1«  fil>ri- 
natea  blood  which  had  been  Buojected  to  a  temperature  of  5.r>°  <  .  during  K)  miniiti •«. 
The  specimen  had  been  drawn  from  caoe  1 1, 16  hours  before.  The  result  «,f  tin-  inj«(  - 
.vaa  entirely  negative,  as  the  subject  remained  in  perfect  health  during  the  10  days 
following. 


YELLOW 


155 


Case  V. — B.  F.  M.,  Spaniard,  nonimmune,  arrived  at  Habana,  October  6,  1901. 
At  4.45  p.  m.,  October  15,  he  received  a  subcutaneous  injection  of  1.5  c.  c.  of  the  same 
material  that  was  used  in  case  IV.  Result  negative. 

Case  VI. — S.  O.,  Spaniard,  nonimmune,  arrived  at  Habana,  October  7,  1901.  At 
4.50  p.  m.,  October  15,  he  was  given  a  subcutaneous  injection  of  1.5  c.  c.  of  the  same 
material  that  was  used  in  cases  IV  and  V.  No  rise  of  temperature  or  other  symptoms 
of  ill  health  followed  this  injection. 


We  desire  to  invite  attention  to  the  fact  that  the  four  subjects  whose 
protocols  have  been  given  above  were  young  Spaniards  who  arrived 
at  Habana  at  a  time  when  yellow  fever  was  not  present  in  the  city; 
that  they  were  carried  from  the  quarantine  camp,  at  Triscorma,  across 
the  bay,  direct  to  Columbia  Barracks,  near  Quemados,  Cuba,  where 
they  were  kept  for  seven  full  days  prior  to  inoculation;  and  that  after 


156  YELLOW    11 

inoculation  they  were  kept  under  <-K»o  daily  observation  for  the 
further  j  f  10  days,  during  \\hirh  time  both  temperature  and 

pulse  were  recorded  every  thin!  hour.  Since  under  tlu^e  circum- 
stances each  of  the  three  nonimmunes  (cases  IV,  V,  and  V 1 )  received. 
without  any  disturbance  to  health,  double  the  quantity  of  heated  and 
partially  defibrinated  blood  that  sullued  \\hen  un heated  to  cause  an 
attack  of  yellow  fever  in  case  111.  it  follows  that  the  specific  a*:ent 
present  in  "the  blood  in  yellow  fever  is  destroyed,  or,  at  least  markedly 
attenuated,  by  a  temperature  of  55°  C.  maintained  for  10  minutes. 

(C)  THE   DILUTED  AND  FILTERED  SERUM. 

Cote  VIL—P.  H.f  American  soldier,  nonimmune,  received  at  11  a.  m.  Octob< : 
1901 ,  a  subcutaneous  injection  of  3  c.  c.  of  the  serum  filtrate,  representing  1 .  "> 
undiluted  serum  101  hours  after  the  blood  had  been  druv.  I      He  rein. 

in  good  health  until  3  p.  m.  October  19,  an  interval  of  four  days  and  f»ur  I 
his  face  appeared  flushed  and  his  eyes  somewhat  injected.    His  temperature  at  this 
time  was  101°  F.,  his  pulse  80.    He  did  not  com  plain  of  headache  or  other  pa  in 
this  ho'ur  his  temperature  declined,  until  at  12  o'clock  midnight  it  registered  98°  F.. 
pulse  72.    October  20,  9  a.  in.,  temperature  100.8°  F..  pulse  TS.     Face  more  suffused 
and  slight  headache  complained  of.    Fever  continued  on  the  21st,  with  more  marked 
flushing  of  the  face  and  injection  of  the  eyes.    The  height  of  the  primary  febrile  j 
yam  was  reached  at  6  p.  m.  October  21.     Remission  occurred  at  9  a.  m.  O<  t«>) 
when  the  temperature  dropped  to  98.8°  F.,  pulse  64.     Tin  r  iM  hem 

was  followed  py  a  secondary  febrile  paroxynn  of  1-  hours'  duration.     On  tli 
blood  was  oozing  from  the  lower  gums  and  the  eyeballs  were  tinged  with  y» -11"\\ . 
Albumin  appeared  in  the  urine  on  the  fourth  day.    The  patient  was  vir-itcd  'by  th<> 
board  of  experts  and  the  diagnosis  of  yellow  fever  confirmed.     Examine 
dried  blood  for  malarial  parasites  was  negative.    The  patient  recovered.     (Oi.irt  I V.  i 

Case  VIII. — A.  W.  C.,  American  soldier,  nonimmune,  was  also  given  at  11.05  a.  m. 
October  15,  1901,  a  subcutaneous  injection  of  3  c.  c.  of  the  diluted  and  filtered  serum. 
being  the  equivalent  of  1.5  c.  c.  of  the  undiluted  serum,  10J  hours  after  the  blood  had 
been  drawn.    He  remained  in  his  usual  health  until  about  noon,  October  1!>.  at  which 
time  he  felt  "out  of  sorts"  and  ate  but  little  dinner.    This  was  4  days  and  1  hour 
the  injection.     During  the  afternoon  he  lay  down  and  slept  until  :*  p.  m..  when  he 
awoke  with  a  severe  headache  and  backache.    His  face  was  flushed.    Temperature 
103.6°  F.,  pulse  102.    At  this  hour  his  face  and  eyes  were  deeply  congested,  and  from 
this  time  his  symptoms  were  characteristic  of  the  disease.    On  the  23d  his  eye- 
quite  yellow  and  general  jaundice  followed  later.     No  albumin  was  found  in  this 
patient's  urine.     He  was  seen  by  the  board  of  experts  and  his  illness  pronoiu 
typical  case  of  yellow  fever.    Careful  examination  of  the  dried  blooa  for  malarial 
parasites  was  negative.    The  patient  made  a  good  recovery.    (Chart  V.) 

Case  IX. — J.  R.  B.,  American,  nonimmune,  at  2.30  p.  m.  October  15,  1901,  was 
given  a  subcutaneous  injection  of  3  c.  c.  of  the  diluted  and  filtered  pcrum.  equal  to 
1.5  c.  c.  of  the  undiluted  serum.  Fourteen  hours  had  elapsed  since  the  blood  had 
been  drawn  from  Case  11. 

This  injection  was  followed  by  no  symptoms  of  physical  disturbance,  until  .".  p.  m 
October  19,  an  interval  of  four  days  and  a  naif  hour,  when  his  temperature  was  99 
pulse  92.    He  complained  of  headache  and  flashes  of  heat,  with  slight  p.iiu  b. 
the  shoulders,  symptoms  which,  the  subject  stated,  were  a  uite  unu>ual  to  him.     At  !» 
p.  m.  temperature  98.4°  F.,  pulse  84.    There  was  n<>  further  febrile  dist urban' 
the  day  following  the  subject  was  in  his  usual  good  health. 

We  thus  observe  that  of  3  nonimmune  individuals  who  n •< •< -ived 
subcutaneously  an  injection  of  filtered  blood  serum  derived   from 
case  II  of  this  report,  2  developed  an  unmistakable  attack  of  yellow 
fever,  after  a  penod  of  incubation  of  98$  hours  and  UK)  hours  re 
tively,  while  in  1  case  the  result  must  be  regarded  as  negative, 

As  already  stated,  the  serum  used  for  these  inoculations  hud  been 
slowly  filtered  through  a  new  Berkefeld  laboratory  filter.  As  soon 
as  possible  thereafter  the  filter  was  resterili/ed  by  steam  and  thor- 
oughly tested  as  to  its  effectiveness  in  preventing  the  passive  of 
bacteria.  For  this  purpose  a  recent  bouillon  culture  of  Staph  /, 


YELLOW   FEVER. 


157 


pyogenes  aureus  was  used,  of  which  50  c.  c.  were  passed  through  the 
niter.  The  filtrate  thus  obtained  was  transferred  hi  quantities  of 
10  c.  c.  to  each  of  two  flasks  con taining  200  c.  c.  of  sterile  bouillon,  which 
were  incubated  at  37°  C.  for  4  days  and  thereafter  kept  at  room 
temperature  for  10  days  longer,  at  the  end  of  which  tune  no  growth 
had  occurred.  It  appears,  therefore,  that  the  filter  used  for  the 
filtration  of  the  blood  serum  in  case  II  was  to  be  relied  upon  for 
the  delivery  of  a  bacteria-free  filtrate. 

The  production  of  yellow  fever  by  the  injection  of  blood  serum 
that  had  previously  been  passed  through  a  filter  capable  of  removing 
all  test  of  bacteria,  is,  we  think,  a  matter  of  extreme  interest  and 
importance.  The  occurrence  of  the  disease  under  such  circumstances, 
and  within  the  usual  period  of  incubation,  might  be  explained  in 
one  of  two  ways,  viz,  first,  upon  the  supposition  that  the  serum 
filtrate  contains  a  toxin  of  considerable  potency;  or,  secondly,  that 


\        STOcc      \ 


\        J160t.c     \        60Ofc.     \_ 


CHAKT  IV.—  Yellow  fever,  produced  by  Injection  of  1.5  cc.  of  filtered  blood-serum. 

4  hours. 


Incubation,  4  days, 


the  specific  agent  of  yellow  fever  is  of  such  minute  size  as  to  pass 
readily  through  the  pores  of  a  Berkefeld  filter. 

In  favor  of  the  supposition  that  in  yellow  fever  an  active  toxin  is 
present  in  the  blood  may  be  cited  the  early  and  well-marked  jaun- 
dice; the  free  hemorrhage  from  the  mucous  membranes  of  the 
mouth  and  stomach,  doubtless  due  to  profound  changes  in  capillary 
vessel  walls;  the  rapid  progress  of  the  disease  to  a  fatal  termination, 
the  advanced  fatty  degeneration  of  the  hepatic  cells,  as  well  as  the 
marked  parenchymatous  changes  found  in  the  kidneys.  f  present 
in  the  blood  this  toxin  would  in  all  likelihood  be  found  in  the  serum 
filtrate  obtained  from  the  blood,  and  if  injected  in  sufficient  quantity 
might  induce  an  attack  of  yellow  fever  in  a  susceptible  individual 
after  the  usual  period  of  incubation.  In  this  respect  it  would  bear 
analogy  to  the  production  of  tetanus  in  the  human  being,  after  the 
usual  period  of  incubation  of  this  disease  by  the  subcutaneous 
injection  of  a  very  small  quantity  of  tetanus  toxin,  as  reported 
by  Nicolas  (7)  in  1893,  and  more  recently  by  Bolton,  Fisch,  and 
Walden  (8). 


15S 


YELLOW     FKVK.R. 


Against  the  view  that  a  toxin  is  present  in  tho  serum  filtrate,  we 
invite   attention   to  the  innocuonsness   of   the   nartially   deiibrinated 
blood  when  heated  to  55°  (\  for  10  minute-,  assnown  by  the  ne^ati\ e 
results  in  cases  IV,  V,  and  VI.      Here  the  toxin,  which  mu-t  have 
-ent  in  i  ust  the  same  quantity  as  in  the  sen  mi  lilt  rate  obtained 
from  this  blootf,  appears  to  nave  been  completely  destroyed  by  the 
temperature  above  mentioned.     Now,  although  certain  bacteria  are 
dot  roved  by  this  temperature,  as  yet  we  know  of  no  bacterial  l 
that  is  rendered  inert  by  such  a  low  decree  of  heat  continued  f< 
short  a  time.      The   tetanus  toxin,   which   h,  found   to  be   the 

most  sensitive  (bus  far  requires,  according  to  Kitasato,  a  tempera- 
ture of  60°  C.  for  20  minutes,  or  5r>°  (\  for  U  hours,  in  order  to  destroy 
its  activity . 

As  a  further   te>t    and   in   order  to  determine   \\hethcr  the    serum 
filtrate  contained  something  more  participate  than  a  soluble  toxin. 


CHART  V.— Yellow  fever,  produced  by  injection  of  1.5  cc.  of  filtered  blood  serum.    Incubation,  4  days, 

1  hour. 

we  availed  ourselves  of  the  opportunity  of  ol»er\  inur  the  ell'cct  that 
would  follow  the  transference  to  a  third  individual  of  blood  drawn 
from  one  of  the  patients  whose  attack  had  been  occasioned  by  the 
injection  of  1.5  c.  c.  of  serum  filtrate  (case  VII).  If  under  i 
circumstances  it  would  be  found  that  the  injection  of  a  -mall  quantity 
of  blood  was  followed  by  an  attack  of  vellow  fever  in  a  thud  indi- 
vidual, the  evidence  would  point  in  tne  strong  M  manner  to  the 
presence  of  the  specific  agent  of  the  disease  in  such  blood,  since  we 
c  an  hardly  believe  that  a  toxin  which  had  undergone  so  great  a 
dilution  in  the  body  of  the  second  individual  would  still  be  capable 
of  producing  the  disease. 

Ca»e  X. — October  22,  1901,  3  p.  m.,  J.  M.  B.,  American,  nonimmuno,  who  on 
October  15,  1901,  at  2.30  p.  m.,  had  been  injected  with  1.5  c.  c.  of  serum  filtruN-  wiih 
negative  result  (vide  case  IX),  and  who  mill  <li -in -<l  to  have  his  immunity  further 
tested,  waff,  at  the  beginning  of  thin,  the  eighth  day  after  his  former  inoculation,  given 


YELLOW    FEVER. 


159 


a  subcutaneous  injection  of  1.5  c.  c.  of  blood  drawn  from  the  venous  circulation  of 
case  VII  early  in  the  fourth  day  of  the  disease.  At  the  time  of  inoculation  the  subjects' 
condition  was  quite  normal.  October  23,  3  p.  m.,  after  an  incubation  period  of  just 
24  hours,  he  complained  of  frontal  and  slight  basal  headache  and  some  pain  between 
the  shoulders.  His  temperature  was  99.6°  F.  and  pulse  100.  At  6  p.  m.,  temperature 
100.4°,  pulse  100.  Pain  in  the  back  quite  severe.  At  10.15  p.  m.,  he  sufferecfa  slight 
chill.  On  the  following  morning  the  face  was  flushed  and  the  eyes  and  gums  injected ; 
there  was  sharp  frontal  headache  and  some  photophobia.  The  height  of  the  primary 
paroxysm  was  reached  at  the  end  of  23  hours.  Remission  occurred  at  9  a.  m.,  October 
25,  and  was  followed  by  a  second  febrile  paroxysm  of  45  hours'  duration.  On  the 
third  day,  during  the  secondary  fever,  the  patient  presented  the  typical  picture  of  a 
mild  case  of  yellow  fever;  the  face  was  deeply  flushed,  eyes  well  injected  and  slightly 
yellow;  there  was  sharp  headache,  and  epigastric  tenderness  and  pain  in  the  lower 
extremities.  Heller's  test  showed  albumin  in  the  urine  drawn  on  the  fourth  day. 
His  fever  subsided  on  the  later  day  and  he  made  a  prompt  recovery.  The  case  was 
seen  by  the  board  of  experts  and  the  diagnosis  confirmed.  (Chart  VI.) 

In  considering  this  individual's  attack,  his  infection  must  be 
attributed  either  to  the  injection  of  the  serum  filtrate  derived  from 
case  II,  in  which  event  the  onset  of  his  disease  was  postponed  until  the 
commencement  of  the  ninth  day  after  inoculation,  or  to  the  injection 


?\      23*  24'*  2  '* 26* 

\AM  I  JW.    \  ~AM.  I  f.Jf.    I  AJ€  I  f*f.  I  A-.M.  I  f.A 


CHART  IV.— Yellow  fever,  produced  by  injection  of  1.5  cc.  of  blood.    Incubation,  24  hours. 

of  blood  obtained  from  case  VII,  after  a  period  of  incubation  of  24 
hours. 

In  our  own  experience  (10)  and  that  of  Guiteras  (11)  of  22  cases 
of  experimental  yellow  fever,  following  the  bite  of  the  mosquito, 
in  which  the  period  of  incubation  was  definitely  and  accurately 
ascertained,  the  longest  period  was  6  days  and  1  hour,  and  the  shortest 
period  2  days  and  13  hours.  If  we  take  the  cases  produced  by  the 
injection  of  blood,  7  in  number,  exclusive  of  the  case  under  considera- 
tion, the  longest  period  was  5  days  and  2  hours  (case  III  of  this 
report)  and  the  shortest  41  hours. 

In  view  of  these  data,  we  believe  we  are  justified  in  expressing 
the  opinion  that  the  source  of  infection  in  case  X  must  be  attributed 
to  the  injection  of  blood  drawn  from  case  VII,  rather  than  to  the 
injection  of  the  filtered  serum  derived  from  the  blood  in  case  II;  and 
further,  that  the  blood  in  case  VII  contained  the  specific  agent  of 
yellow  fever,  which  had,  therefore,  passed  through  the  filter  along 
with  the  filtrate  with  which  this  latter  individual  had  been  inoculated. 

The  important  questions  which  naturally  arise  from  the  foregoing 
experiments  must  be  left  for  the  future,  observations  to  determine. 


160  YELLOW   FEVBB. 


BIBLIOGRAPHY. 

(1)  The  Etiology  of  yellow  Fever — An  Additional  Note.    Journal  American  Medical 
Association,  February  16.  1901. 

(2)  Experimental  Yellow  Fever.    Transa  the  Association  of  Ameru -an 
Physicians.    Vol.  xvi  1901. 

(3)  Berichte  der  Kommisaion  eur  Erforechung  der  Maul-und  Kkne&wncb 
dem  Inatitut  fur  Infectionskrankheiten  in  Berlin.    Centnilblatt  fur  Bicteriologie, 
Band  9-10.  p.  371-391. 

(4)  Berichte  der  Kommission  zur  Erforechung  dor  Maul-un.l  Klauonscu. •!»••. 
Centralblatt  fur  Baetoriologie  und  Parasitenkunde,  Band  xxiv,  No.  15- . 

(5)  Experimental  Yellow  Fever  at  the  Inoculation  Station  of  the  Sanitary  Depart 
ment  of  Havana,  with  a  view  to  Producing  Immunization.    "American  Median*. " 

I ,  No.  21,  November  23,  1901. 

(6)  "Experimental  Yellow  Fever."    Transactions  of  the  Association  of  Anx 

1.  xvi,  1901. 

(7)  Sur  un  cas  de  tetanus chez  I'homme  par  inoculation  accidentelleprpduitaBoluhK' 
du  bacille  de  Nicolaier.    Comtes  Rendus,  etc.,  de  la  Societe  Biologic.    Ton 
1893,  pp.  844-46. 

(8)  Report  of  the  Commission  appointed  to  investigate  the  cases  of  tetanus  in  St. 
Louis,  following  the   administration  of   diphtheria  antitoxin.    St.  Louis  Medical 

•  •w,  November  23,  1901. 

(9)  Zeitschrift  fur  Hygiene,  1901,  Bd.  x,  S.  283. 

(10)  Loc.  (it 

(11)  Loc.  cit. 


CHAPTER  8. 

RECENT  RESEARCHES  CONCERNING  THE  ETIOLOGY,  PROPAGA- 
TION, AND  PREVENTION  OF  YELLOW  FEVER,  BY  THE  TJNITED 
STATES  ARMY  COMMISSION  (THREE  CHARTS). 

By  WALTER  REED,  M.  D.,  Surgeon,  United  States  Army,  President  of  the  Commission. 
[From  The  Journal  of  Hygiene,  Vol.  II,  No.  2,  April,  1902.] 

The  efficient  control  of  the  spread  of  yellow  fever  is  a  matter  of 
such  vast  practical  importance,  both  from  the  hygienic  and  com- 
mercial point  of  view — not  only  for  the  countries  where  this  disease 
prevails  as  an  epidemic,  but  also  for  those  in  which,  after  importa- 
tion, it  may  assume  epidemic  proportions — that  it  has  seemed  appro- 
priate to  bring  together  in  this  paper  a  summary  of  the  work  thus 
far  accomplished  by  the  United  States  Army  Commission1  on  the 
island  of  Cuba,  during  the  years  1900  and  1901,  in  order  that  English 
and  Colonial  readers  who  have  not,  perhaps,  had  access  jto  the 
original  contributions  published  in  different  American  journals,  may 
be  able  to  form  an  intelligent  opinion  concerning  the  permanent  value 
of  this  work.  It  will  also  afford  opportunity  for  recording  the  more 
recent  confirmatory  observations  made  by  others  concerning  the  mode 
of  transmission  of  yellow  fever  discovered  by  the  commission,  and 
for  calling  attention  to  the  results  already  obtained  by  the  United 
States  Army  Medical  Department  in  the  suppression  or  this  disease, 
especially  in  the  city  of  Habana,  through  the  enforcement  of  sanitary 
measures  based  on  these  later  researches. 

The  American  commission  was  organized  in  May,  1900,  and  began 
its  investigations  during  the  following  month  (June),  being  equipped 
with  suitable  laboratory  facilities  for  practical  work,  both  at  the 
military  garrison  of  Columbia  Barracks,  near  Quemados,  Cuba,  and 
also  in  the  city  of  Habana.  As  yellow  fever  was  already  prevailing 
at  the  time  of  our  arrival  in  Cuba  suitable  material  for  the  scientific 
study  of  this  disease  was  immediately  available. 

THE  ETIOLOGY  OF  YELLOW  FEVER. 

Before  giving  the  results  of  our  investigations  it  may  be  well  to 
recall  the  situation  as  regards  the  etiology  of  yellow  fever  at  that 
time.  Briefly  it  may  be  said  that  the  claims  of  all  investigators  for 
the  discovery  of  the  specific  agent  of  yellow  fever — since  modern 
bacteriological  methods  had  come  into  use — had  been  disproved  by 
the  exhaustive  observations  of__Sternbergjl),  published  in  1890,  ex- 
cept that  made  by  Sanarelli  (2)  for  a  small,  motile  bacillus  isolated 
by  him  from  the  blood  drawn  during  life  in  2  of  6  cases  of  yellow 
fever,  and  from  the  blood  and  organs  after  death  in  7  of  12 
cases  of  this  disease  (58  per  cent),  studied  at  Montevideo  and  Rio  de 

i  The  members  of  this  commission  were  Maj.  Walter  Reed,  Surgeon,  United  States  Army,  and  Drs. 
James  Carroll,  A.  Agramonte,  and  the  late  Dr.  Jesse  W.  Lazear,  Contract  Surgeons,  United  States  Army. 

79965°— S.  Doc.  822,  61-3 11  161 


162  YELLOW   FEVEB. 


Janeiro.  Brazil.  The  results  obtained,  howm-or.  by  those  who  had 
promptly  undertaken  to  investigate  Sanarelli's  claim  for  the  specific 
character  of  BaciQua  icteroides,  seemed  to  show  a  lack  of  agreement 
such  as  has  never  been  reported,  as  far  as  the  writer  can  recall,  in 
connection  \\ith  the  supposed  specific  cause  of  any  of  the  other  a<  -me 
infections.  Thn  :  d  and  Woodson  (  :>)  had,  during  the 

enidemic  of  1V»7  in  New  Orleans,  La.,  isolated  a  haeillns.  claimed  by 
them  to  he  identical  with  />.  tcteroid**,  from  the  venons  Mood  in  1 
out  of  ")  eases,  and  from  yellow  IV  aveTH  in  32  nut  di 

cases  (8'J  per  cent\  PoHier  (4),  wurldng  in  the  Same  city  and  during 

the    same    epid.  uld    only    obtain    this    bacillus    :>   time 

51    autopsies,   and   failed   to  obtain  it  at  all  in  cultures  made  from 
venous  blood  during  life  in  H)  rases.     Again,  \\hile  Wn-din  and 
Geddings  (5),  in  the  city  of  Habana,  were  able  to  eultix  ate  />'.  <<f<  / 
from  blood  withdrawn  frm  the  lobe  of  the  ear,  "not  earlier  than  the 
third  day  of  the  disease"  in  13  of  14  cases  (92.8  per  cent   .  and  to 
iind  it  in  S.V7  per  cent  of  their  necroo-ie-.  Agraimmte  (ID.  stiid\hiLr 
the  disease  on  the  island  of  Cuba,  failed  to  isolate  B.  icteroides  in  a 
single  instance  from  blood  drawn  from  the  lobe  of  the  ear-  in 
or  from  the  blood  drawn  from  a  vein  at   the  bend  of  the  elbow  in 
;>l  coses  at  various  stages  of  the  disease.     The  lattef  ob&ctrV&r,  ho\\- 
ever,  reported  finding  this  hneillus  at  autopsy  in  1  1  of  ;*5  eases 
per  cent).     Without  goin.tr  further  into  detail,  we  may  .-  i    the 

residts  obtained  by  Lutz  (7)  and  de  Lacerda  and  Kai  n  Bra/il. 

and  by  Matienzo  (9)  in  Mexico,  were  equally  conflicting  and  nn- 

TV. 

ruder  the<e  CIK  umstances  it  seemed  to  the  members  <  -m 

mission  of  the  first  importance  to  give  their  entire  attention  to  the 
bacteriological  study  of  the  blood  of  those  sick  with  yellow  fever  and 
of  the  blood  and  organs  of  yellow-fever  cadavers,  having  especially  in 
view  the  isolation  of  B.  icteroides.     We  were  thus  able  during  »!une. 
July,  and  August  to  take  repeated  cultures  from  the  blood  during  life 
in  IS  cases  of  yellow  fever,  adopting  the  usual  method  employed  in 
withdrawing  blood  from  a  vein  at  the  bend  of  the  elbow,  and'i 
ferring  the  blood  at  once,  in  quantities  of  0.5  c.  c.,  to  each  of  several 
tubes  containing  10  c.  c.  of  nutritive  bouillon  which  were  afterward- 
incubated  at  37°  (\  for  a  period  of  one  week.     In7case>.  1  of  which 
were  designated  as  "mild"  yellow  fever  and  3  as  "well-mar1 
yellow  fever,  only    1    culture  was  made  from  the  blood   in    each 
case,  viz,  in   2   cases  on   the  first   day;   in    1    case   on    the  second 
day;  in  3  cases  on  the  third  day;  and*m  1  case  on  the  fourth  da\ 
In   the   remaining   11    cases,   diagnosed   as  "severe"  yellow   I'. 
of  whom  4  died,  more  frequent    cultures  were  taken  from  tl 

•  varying  from  2  to  (\  cultures  on  as  many  different  day-  of  the 
disease.     In  2  of  the  fatal  cases  cultures  were  made  each  day  from  the 
commencement  of  the  attack  and  including  the  day  on  wliieh  d< 
occurred. 

The  negative  result  of  these  numerous  cultures  taken   from   the 
blood  of  ea^e-  of  yellow  fever.  a<  reirard-  the  presence  of  /.'.    - 

reported  in  a  "Preliminary  note"  pre-enied  at  the  meeting  «•• 

.'i  Public  Health  Association   (10),  held  in   Indiai,  Ind.. 

•  her  22-26,    I'.iOO.     To   the-e    is   .  ;i  :m    now  add  r,  other 
cases,  or  a  total  of  1M.   from   which   blood  culture-  have   been   made 
during  life  with  negative  result-. 


YELLOW    FEVER.  163 

The  importance  of  this  negative  finding  as  regards  the  growth  of 
any  specific  bacterium  will  be  better  appreciated  when  it  is  seen,  as  I 
shall  soon  have  occasion  to  point  out,  that  yeUow  fever  may  be  pro- 
duced in  nonimmune  human  beings  by  the  subcutaneous  injection  of 
a  small  quantity  (0.5-2  c.  c.)  of  blood  withdrawn  from  the  venous 
circulation  of  a  patient  suffering  with  this  disease. 

In  addition  to  the  results  above  recorded,  the  careful  study  of  11 
autopsies  was  equally  barren  as  to  the  presence  of  any  particular 
micro-organism,  although  the  quantity  of  material  with  which  our 
tubes  were  inoculated  was  greater  than  is  usually  made  use  of  at 
autopsies. 

In  a  word,  then,  the  careful  bacteriological  study  which  the  com- 
mission had  made  in  cases  of  yellow  fever  had  given  no  indications 
as  to  the  presence  of  the  specific  agent  of  this  disease.  The  same  may 
be  said  concerning  the  result  of  numerous  microscopic  examinations 
of  fresh  and  stained  specimens  of  blood  which  we  had  in  the  mean- 
while studied  with  a  view  of  finding  possibly  some  intracellular  or 
extracellular  body.  Apparently  no  body,  bacterial  or  protozoan, 
which  could  be  brought  into  view  with  a  one-twelfth  Zeiss  immersion 
objective,  was  present  in  the  blood  of  these  cases. 

Although  displaced  from  the  order  in  which  the  following  observa- 
tions were  made,  it  will  be  best  to  present,  at  this  time,  the  results  of 
the  experiments  which  were  later  carried  out  by  the  commission  on 
nonimmune  human  beings  by  means  of  the  subcutaneous  injection  of 
blood,  withdrawn  during  the  active  stage  of  the  disease,  as  these  results 
bear  so  directly  upon  the  subject  which  we  are  now  considering,  viz, 
the  etiology  of  yellow  fever. 

The  only  reference  that  I  can  find  in  the  literature  relative  to  an 
attempt  to  convey  yellow  fever  in  this  way  is  cited  by  Sternberg  (11),       / 
who  states  that  at  Veracruz,  Mexico,  in  1887,  he  saw  Dr.  Ruis  inject 
into  a  nonimmune  individual  a  hypodermic  syringeful  of  blood  drawn 
from  a  case  of  yellow  fever  on  the  eighth  day  of  the  disease.     The 
result  was  negative,  as  was  also  the  result  of  two  other  attempts     / 
related  to  him  by  Ruis. 

Our  own  observations,  undertaken  for  the  purpose  of  ascertaining 
whether  an  attack  of  yellow  fever  could  be  induced  m  a  second  indi- 
vidual by  the  injection  of  a  small  quantity  of  blood,  embrace  experi- 
ments made  on  12  American  soldiers  and  Spanish  immigrants,  all 
nonimmune  individuals. 

These  observations  may  be  divided  into  the  folio  whig  classes: 

(1)  Injection  of  the  fresh  blood  taken  from  a  vein  at  the  bend  of 
the  elbow.  (2)  Injection  of  partially  defibrinated  blood.  (3)  Injec- 
tion of  partially  defibrinated  blood  heated  for  10t  minutes  at  55  C. 
(4)  Injection  of  blood  serum  previously  diluted  with  sterilized  water 
and  filtered  slowly  through  a  Berkefeld  laboratory  filter. 

The  table  following  (I)  gives  the  results  of  these  several  inoculations. 


164 


TABLE  I. 


So.  of 
CM*. 

Quantity  and  material  used. 

Day  of 

diaMM. 

Date  of 

:::.•,  -Lit  )OB 

Result. 

Date  of 
attack. 

.!! 
if 

VII 

*$ 

I 

XII 

BtMBd  . 
do 

Dec.  26,1000 
Jan.     4,1901 
Jan.     8,  1901 
Jan.   22,1901 
'  ...     M,1901 

. 

...do 
...do 
..do 

Negative.. 
...do.... 

Jan. 
11,1801 

19.  1901 

f  rash  blood 

Uti  : 

fresh  blood... 

...do 

ittd  blood 

..partially".! 
for  10  minutes  at  65*  C. 

S.»-MO:IS  \,«    \1I 

...do 

1.5  c.  r.  of  fi 

S-iine  M  No    \ 

.do.. 

l^'iri.'  -i-  No    \ 

do 

[2  c  c.  fresh  blood                                 

Oct.   22,1901 

By  an  examination  of  this  table  it  will  be  seen  that  of  the  sc 
individuals  who  received  subcutaneoualy  the  fresh  or  partially  defi- 
brinated  blood  in  quantities  of  0.5-2  c.  c.,  six  (85. 7  per  rent)  de\ «  1 
an  attack  of  yellow  fever  within  the  usual  period  of  incubat i< .n  of  the 
disease. 

These  results  are  of  very  great  interest  as  demonstrating  that  the 
specific  agent  of  yellow  fever  is  present  in  the  blood,  at  least  during  the 
first,  second,  and  third  days  of  the  attack. 

Another  important  point  brought  out  by  these  experiments 
that  the  blood  which  conveyed  the  disease  did  not  contain  any 
terium  which  would  grow  on  our  usual  laboratory  media. 

In  order  to  establish  this  fact,  as  soon  as  blood  had  been  injected 
into  the  nonimmune subject,  additional  blood  was,  at  onee.  withdrawn 
in  considerable  quantity  and  transferred  to  tubes  of  nutritive  bouillon. 
In  one  instance,  where  2  c.c.  of  blood  had  been  drawn  into  the  syringe. 
0.5  c.  c.  of  this  sufficed,  when  injected,  to  produce  a  severe  al 
yellow  fever,  after  73  hours'  incubation,  while  the  remaining  1.5  <  .  <  . 
transferred  immediately  to  four  tubes  of  bouillon  gave  no  growth. 
except  that  from  one  tube  we  isolated  on  the  fourth  day  > 
coccus  pyogenes  citreus,  found  by  us  to  be  a  common  skin-<  ontaini- 
nating  organism  in  Cuba. 

Table  If  urther  shows  that  the  specific  agent  contained  in  the  hi 
is  destroyed  or  attenuated  by  heating  the  latter  at  55°  C.  for  in  min- 
utes, so  that  the  injection  of  1.5  c.  c.  of  this  heated  blood  \\ 
less  (cases  VII.  VIII,  and  IX),  while  the  injection  of  0.75  c.  c.  of  the 
same  blood  unneated  sufficed  to  promptly  induce  an  attack  of  yellow 
fever  in  a  "control"  individual  (case  VI). 

Of  not  less  interest  was  the  fact  brought  out  by  these  observat  i 
that  yellow  fever  can  be  produced  by  the  injection  of  a  small  quant  ity 
of  bacteria-free  serum  filtrate,  obtained  by  passing  the  diluted  serum 
through  a  Berkefeld  laboratory  filter  (cases  X  and  XI  >,  and  further 
that  the  blood  of  a  case  of  yellow  fever,  thus  produced,  when  injected 
into  a  third  nonimmune  subject  will  promptly  bring  about  an  attack 
of  this  disease  (case  XII );  thus  demon st  rat  ing  t  hat  the  specific  a 
of  yellow  fever  can  find  its  way  through  the  pores  of  a  filter  which  ordi- 
narily serves  to  prevent  the  passage  of  all  known  bacteria. 

I    have  elsewhere  (12)  in  conjunct  ion   with  one  of  my  collea 

roll)  discussed  the  facts  here  presented  more  at  length  and  \\ill 
limit  myself,  therefore,  to  the  remark  that  these  experiments  app< -;«r 


YELLOW   FEVER.  165 

to  indicate  that  yellow  fever,  like  the  foot-and-mouth  disease  of 
cattle,  is  caused  by  a  micro-organism  so  minute  in  size  that  it  might 
be  designated  as  ultramicroscopic. 

THE  PROPAGATION  OF  YELLOW  FEVER. 

Prior  to  the  time  at  which  the  foregoing  observations  were  made 
the  commission  had  already  turned  its  entire  attention  to  the  possible 
solution  of  the  problem  of  the  propagation  of  yellow  fever,  being 
induced  thereto,  not  only  by  the  fruit lessness  of  the  investigations 
made  thus  far  along  bacteriological  lines,  but,  also,  by  reason  of  cer- 
tain facts  which  seemed  to  call  for  a  better  interpretation  than  had 
hitherto  been  accorded  them. 

Without  entering  into  details,  I  may  say  that,  in  the  first  place,  the 
commission  saw,  with  some  surprise,  what  had  so  often  been  noted  in 
the  literature,  that  patients  in  all  stages  of  yellow  fever  could  be  cared 
for  by  nonimmune  nurses  without  danger  of  contracting  the  disease. 
The  noncontagious  character  of  yellow  fever  was,  therefore,  hardly  to 
be  questioned. 

In  the  second  place,  it  had  been  observed  that  patients  discharged 
from  the  wards  during  early  convalescence  could  be  brought  into 
intimate  association  with  nonimmune  individuals  without  thereby 
establishing  fresh  foci  of  the  disease.  This  did  not  seem  to  indicate 
that  any  specific  agent  was  present  in  the  excreta  of  the  sick. 

Again,  it  has  been  noted  that  in  certain  cases  of  this  disease  no 
growth  had  been  obtained  on  the  ordinary  laboratory  media,  either 
by  frequent  cultures  from  the  blood  during  life  or  from  the  blood 
and  organs  after  death. 

Further,  in  the  course  of  an  investigation  which  the  commission 
were  able  to  make  during  the  last  week  of  July,  1900,  concerning  the 
origin  and  spread  of  a  small  epidemic  of  yellow  fever  that  had 
appeared  in  a  military  garrison,  numbering  about  900  men,  at  Pinar 
del  Rio,  Cuba,  they  had  seen  that  by  reason  of  the  false  diagnosis  of 
"pernicious  malarial  fever"  which  had  been  given  to  these  cases  no 
disinfection  of  bedding  or  clothing  had  been  carried  out;  and  yet 
there  was  no  indication  that  this  neglect  had  contributed  in  the 
least  to  the  spread  of  the  disease;  nor  had  any  harm  come  to  those 
nonimmunes  who  had  slept  in  the  beds  vacated  by  the  sick,  or 
washed  the  supposedly  infected  garments  of  those  who  had  recovered 
or  died  of  this  disease. 

Putting  these  various  data  together,  it  seemed  probable  that  more 
progress  might  be  made  if  attention  should  be  turned  to  the  mode  of 
transmission  of  yellow  fever,  especially  as  our  own  observations  had 
caused  us  to  seriously  doubt  the  usually  accepted  belief  of  the  con- 
veyance of  this  disease  by  means  of  fomites. 

Then,  too,  the  endemic  curve  of  yellow  fever  in  the  city  of  Habana, 
and  its  well-known  epidemic  curve  in  the  United  States,  appeared  to 
be  more  intimately  associated  with  and  more  affected  by  the  rise  and 
fall  of  the  annual  temperature  curve  than  was  to  be  seen  in  any  of 
the  acute  infections,  except  malarial  fever.  The  peculiar  behavior 
of  this  disease  (if  I  may  use  the  expression)  in  rapidly  spreading  in 
certain  localities,  when  introduced,  as  contrasted  with  its  failure  to 
propagate  itself  in  other  places,  where  the  conditions  for  its  increase 
were  apparently  just  as  favorable,  seemed  to  point  in  the  strongest 


166  VK1,LO\V    KKYKK. 

manner  to  the  necessity  for  some  special  agent  or  intermediate  host 
in  the  dissemination  oi  it-  >pccific  cause.  If  malarial  fever — a  dis- 
ease so  much  affected  by  temperature  condition-  n 'quired  the 
agency  of  a  special  genus  of  mosquito  for  its  propagation ,  as  had  in 
recent  years  oeen  so  brilliantly  worked  out  oy  Ross,  Grassi,  Bas- 
tianelli,  Bignami,  and  others,  it  did  not  seem  unreasonable  to  sup- 
pose that  yellow  fever — a  disease  so  plainly  controlled  by  seasonal 
conditions — might  also  depend  on  some  MK -h  iu:ent  for  its  soread. 
Influenced  by  this  line  of  reasoning:,  the  coimni— ion  l>e«ran.  during 
the  second  week  of  AiiiruM.  I'.MM).  its  observations  relative  to  the 
propagation  of  yellow  fever  by  means  of  the  bite  of  a  certain  species 
of  mosquito — Slegomyia  fa-sdata. 

The  work  alon^  this  Une  was  carried  forward  so  rapidly  t  hat .  within 

30  days,  11    individuals  had  been   bitten  by   infected   Stegom 

of  whom  two  '  developed  well-marked  attacks  of  yello\\  lever  within 

tlit»  UMinl  period  of  incubation,  and  under  such  circumstances  as  to 

i\  dy  t  \.  hide  in  one  case  any  other  possible  source  i  ion. 

Appreciating  fully  the  importance  of  this  discovery  and  in  order  to 
exclude  all  other  possible  sources  of  infection  hi  our  future 
tions.  it  was  now  determined  to  establish  a  special  experimental 
station  where  further  observations  could  be  made  on  noiiimmune 
human  beings,  both  as  to  tlie  propagation  of  yellow  fever  by  means 
of  the  bite  of  the  mosquito  as  well  as  by  exposure  to  tl  inti- 

mate contact  with  infected  clothing  and  bedding,  and  this  under  the 
strictest   enforcement  of   military   quarantine.     With    the  anpr 
and  assistance  of  the  military  governor  of  the  Island  of  Cuba,  this 
experimental  station  was  ready  lor  occupancy  on  November  20,  1900, 
and  was  continuously  occupied  until  March  1,  1901. 

As  the  results  obtained  at  this  station  have  already  been  published 
(13)  in  full  elsewhere,  I  will  here  only  present  a  brief  account,  iii 
the  experiments  with  fomites  and  afterwards  of  those  made  with  in- 
fected mosquitoes. 

ATTEMPTS   AT    INFECTION    BY    FOMITES. 

I  quote  from  a  paper  which  the  writer  presented  for  the  commissi*  >n 
at  tlie  meeting  of  the  Pan-American  Medical  Con^rexs.-  held  in 
Habana,  Cuba,  February  4-7,  1901: 

For  this  purpose  there  was  erected  at  Camp  Lazear  a  small  frame  house  consisting 
of  one  room,  14  by  20  feet,  and  known  as  "  building  No.  1,"  or  the  "infectr 
and  bedding  building."    The  cubic  capacity  of  this  house  was  2,80"  it  was 

tightly  sealed  within  with  "tongued  ana  grooved"  boards,  and  was  w«  11  in  it.  nod  on 
the  outside.  It  faced  the  south  and  was  provided  with  two  small  windows,  ea<  h  _'i;  l»y 
34  inches  in  size.  These  windows  were  Doth  placed  on  the  south  side  of  thr  Imildint:. 
the  purpose  being  to  prevent,  as  much  as  possible,  any  thorough  (in  illation  <>i  tin- 
air  within  the  house.  They  were  closed  by  permanent  wire-screens  of  0.5  mm.  mesh. 
In  addition  a  sliding  glass  sash  was  provided  within  and  heavy  wooden  shut  i» TS  with- 
out; the  latt<-r  intended  to  prevent  the  entrance  of  sunlight  into  the  building,  as  it 
was  not  deemed  desirable  ih  it  tin-  dlrinfocting  qualities  of  ninUgfat,  dfrad  ordflraftd, 
should  at  any  time  be  exerted  on  the  articles  of  clothing  contain*  •«!  within  tl-.i  - 
Entrance  wan  effected  through  a  small  vestibule,  3  by  5  feet,  also  placed  <>n  th<  ;.:h<  rn 
side  of  the  house.  This  vestibule  was  protected  without  by  a  solid  door  ami 
<li\i<l«l  in  its  middle  by  a  wire-screen  door,  swung  on  spring  hinges.  Th<-  inn<  r 
entrance  was  also  closed  by  a  second  wire-screen  door.  In  this  way  the  passage  of 

>  One  of  UMM  OMMt  was  that  of  Dr.  James  Carroll,  Contract  Surgeon,  U.  8.  A.,  a  member  of  the 


YELLOW    FEVER.  167 

mosquitoes  into  this  room  was  effectually  excluded.  During  the  day  and  until  after 
sunset  the  house  was  kept  securely  closed,  while  by  means  of  a  suitable  heating 
apparatus  the  temperature  was  raised  to  92°-95°  F.  Precaution  was  taken  at  the  same 
time  to  maintain  a  sufficient  humidity  of  the  atmosphere.  The  average  temperature 
of  this  house  was  thus  kept  up  at  76.2°  F.  for  a  period  of  sixty-three  days. 

November  30.  1900,  the  building  now  being  ready  for  occupancy,  three  large  boxes 
filled  with  sheets,  pillowcases,  blankets,  etc.,  contaminated  by  contact  with  cases  of 
yellow  fever  and  their  discharges  were  received  and  placed  therein.  The  majority 
of  the  articles  had  been  taken  from  the  beds  of  patients  sick  with  yellow  fever  at  Las 
Animas  Hospital,  Habana,  or  at  Columbia  Barracks.  Many  of  them  had  been  pur- 
posely soiled  with  a  liberal  quantity  of  black  vomit,  urine,  and  fecal  matter.  A  dirty 
"comfortable  "  and  a  much-soiled  pair  of  blankets,  removed  from  the  bed  of  a  patient 
sick  with  yellow  fever  in  the  town  of  Quemados  were  contained  in  one  of  these  boxes. 
The  same  day,  at  6  p.  m.,  Dr.  R.  P.  Cooke,  acting  assistant  surgeon,  United  States 
Army,  and  two  privates  of  the  Hospital  Corps,  all  nonimmune  young  Americans, 
entered  this  building  and  deliberately  unpacked  these  boxes,  which  had  been  tightly 
closed  and  locked  for  a  period  of  two  weeks.  They  were  careful  at  the  same  time  to 
give  each  article  a  thorough  handling  and  shaking,  in  order  to  disseminate  through  the 
air  of  the  room  the  specific  agent  of  yellow  fever,  if  contained  in  these  fomites.  These 
soiled  sheets,  pillowcases,  and  blankets  were  used  in  preparing  the  beds  in  which  the 
members  of  the  Hospital  Corps  slept.  Various  soiled  articles  were  hung  around  the 
room  and  placed  about  the  bed  occupied  by  Dr.  Cooke. 

1  From  this  date  until  December  19,  1900,  a  period  of  20  days,  this  room  was  occupied 
each  night  by  these  three  nonimmunes.  Each  morning  the  various  soiled  articles 
were  carefully  repacked  in  the  aforesaid  boxes,  and  at  night  again  unpacked  and  dis- 
tributed about  the  room.  During  the  day  the  residents  of  this  house  were  permitted 
to  occupy  a  tent  pitched  in  the  immediate  vicinity,  but  were  kept  in  strict  quarantine. 
*  *  *  *  *  *  * 

December  19  these  three  nonimmunes  were  placed  in  quarantine  for  five  days  and 
then  given  the  liberty  of  the  camp.  All  had  remained  in  perfect  health,  notwith- 
standing their  stay  of  20  nights  amid  such  unwholesome  surroundings. 

During  the  week  December  20-27  the  following  articles  were  also  placed  in  this 
house,  viz,  pajamas  suit,  1;  undershirts,  2;  nightshirts,  4;  pillow  slips,  4;  sheets,  6; 
blankets,  5;  pillows,  2;  mattress,  1.  These  articles  had  been  removed  from  the  per- 
sons and  beds  of  four  patients  sick  with  yellow  fever  and  were  very  much  soiled,  as 
any  change  of  clothing  or  bed  linen  during  their  attacks  had  been  purposely  avoided, 
the  object  being  to  obtain  articles  as  thoroughly  contaminated  as  possible. 

From  December  21,  1900,  till  January  10,  1901,  this  building  was  again  occupied 
by  two  nonimmune  young  Americans  under  the  same  conditions  as  the  preceding 
occupants,  except  that  these  men  slept  every  night  in  the  very  garments  worn  by 
yellow  fever  patients  throughout  their  entire  attacks,  besides  making  use  exclusively 
of  their  much-soiled  pillow  slips,  sheets,  and  blankets.  At  the  end  of  21  nights  of 
such  intimate  contact  with  these  fomites,  they  also  went  into  quarantine,  from  which 
they  were  released  five  days  later  in  perfect  health. 

From  January  11  till  January  31,  a  period  of  20  days,  ''building  No.  1"  continued 
to  be  occupied  by  two  other  nonimmune  Americans,  who,  like  those  who  preceded 
them,  have  slept  every  night  in  the  beds  formerly  occupied  by  yellow  fever  patients, 
and  in  the  nightshirts  used  by  these  patients  throughout  the  attack  without  change. 
In  addition,  during  the  last  14  nights  of  their  occupancy  of  this  house  they  had  slept 
each  night  with  their  pillows  covered  with  towels  that  had  been  thoroughly  soiled 
with  the  blood  drawn  from  both  the  general  and  capillary  circulation  on  the  first  day 
of  the  disease,  in  the  case  of  a  well-marked  attack  of  yellow  fever.  Notwithstanding 
this  trying  ordeal  these  men  have  continued  to  remain  in  perfect  health. 

The  attempt  which  we  have  therefore  made  to  infect  "building  No.  1 "  and  its  seven 
nonimmune  occupants  during  a  period  of  63  nights  has  proved  an  absolute  failure. 

INFECTION    BY   MOSQUITOES. 

While  the  experiments  with  fomites  were  being  carried  out  in 
"  Building  No.  1,"  certain  nonimmune  individuals  wfro  were  lodged 
in  tents,  in  a  separate  part  of  the  camp,  were  being  subjected,  with 
their  full  consent,  to  the  bites  of  mosquitoes  which  had  previously  fed 
on  the  blood  of  cases  of  yellow  fever  occurring  in  the  city  of  Havana. 
Thus  during  the  period  from  December  5,  1900,  to  February  7,  1901, 
we  had  subjected  to  this  method  of  infection  12  nonimmune  subjects, 


HiS 


who  had  previously  passed  their  full  record  of  quarantine  in  this 
camp.  Of  these  10,  or  83.3  per  cent,  experienced  attack-  of  yellow 
fever  and  always  within  the  period  of  incubation  of  this  di 

The  following  Table  II  gives  the  necessary  data  concerning  these 
observations : 

TABLE    11 


\        l' 

Days  in 

Inocul 

ilion. 

Mi-tho.t  nf 

i  •        i 

!  i  r  :.  ••  ! 

.if  tnea 

Orte 

cms*. 

isr 

BMT, 

lut.'. 

InoculaUon. 

tattoo 

:n 

boon. 

Result. 

mot* 

cxvunviuv 

I 

n 

16 

o 

2p.m... 
4  p.  in 

Dec.    5,  1900 
Dec.    8,  1900 

Mosquito.... 

m 

137 

Positive  

.do 

ni 

I».v.      Vl'.«i 

m 
1 

VI 

19 
21 
82 
31 

10JOa.m  
4.30  p.  m  
12m.  
10  a.  in 

Dte.    »,1900 
Dec.  11,1930 
Dec.  21.1900 
Jan.     8,1901 

do  

do 

:••  

.do... 

831 

Sl 

do 
do 
do 

11 

VI 

Dec,  I.M'.«N» 
Deo.  i.vi-Mi 
Deo.  26,1900 

VII 
VIII 

22 

09 

8.30  p.  m  

Dte.  10,1900 

Jan.    19.  1901 

do  
.do  

$ 

Positive  
.do... 

VII 
Mil 

Jan.     3.1901 
Jan.   23  1901 

£ 

\u 

74 
6 
78 
25 

10.30  a.  m  
9.30  a.m  
lla.m  
2  p.  m 

Jan,   26,1901 

Jan.   31.1901 

K.'h.     ...  1-..H 
Feb.     7,  1901 

do  
do  
do  
.  ..do  

"¥ 

70 

Negative.  .  .  . 
ive  

.do 

XII 

Feb.    3,  1901 

The  positive  results  obtained,  therefore,  by  this  mode  of  infection 
stand  in  striking  contrast  to  the  negative  experiments  made  with 
fomites.  Indeed,  cases  VIII  and  XI  of  Table  II  had  each  >lept  _'l 
nights  in  the  garments  of  yellow  fever  patients  while  occupan 
'' building  No.  1."  As  they  had  remained  in  perfect  health  at  Camp 
La /ear  for  yet  30  days  longer,  they  were  at  the  expiration  of  this 
time  bitten  by  infected  mosquitoes  solely  for  the  purpose  of  testing 
their  immunity  and  with  the  result  that  an  attack  of  yellow  fever 
promptly  followed  in  each  case. 

It  should  be  borne  in  mind,  also;  that  of  the  nonimmune  re-idem  s 
at  Camp  Lazear,  while  all  lived  under  the  same  hygienic  condition^. 
only  those  individuals  developed  yellow  fever  who  were  purp 
bitten  by  contaminated  mosquitoes,  or  injected  with  the  blood  of 
those  sick  with  this  disease.     Moreover,  the  precision  with  which  the 
infection  of  the  individual  followed  the  bite  of  the  mosquit< 
nothing  to  be  desired  hi  order  to  fulfil  the  requirements  of  a  s< •  lentil ie 
experiment. 

Case  V  of  Table  II  is  of  especial  interest,  when  taken  in  connection 
with  the  failure  to  induce  the  disease  by  contact  with  fomites. 

This  individual,  having  been  quarantined  for  32  days  at  Cami> 
Lazear,  volunteered  to  enter  a  newly  erected  building  in  which 
15  contaminated  mosquitoes  had  just  been  freed.  His  lirM  \  rit 
was  at  noon,  December  21,  1900,  and  the  length  of  his  stay  30  min- 
utes. At  4.30  p.  m.  the  same  day  he  again  entered  this  building  and 
remained  20  minutes.  The  following  day  at  4.30  p.  m.  he  for  the 
third  time  visited  this  room  and  remained  20  minutes.  During 
each  of  these  visits  he  was  bitten  by  mosquitoes.  He  did  not  enter 
the  building  again,  nor  was  he  exposed  to  any  other  source  of  i; 
.  Nevertheless  at  the  expiration  of  3  days  and  2:\  hour 
at  6  a.  m.  December  25,  1900,  he  was  suddenly  seized  with  an  attack 
of  yellow  fever,  which  proved  to  be  severe  in  char.  Th.it  the 

infection  was  occasioned  by  the  bites  of  contaminated  mosqui; 
plainly   shown  by   the  immunity    from    the    disease   enjoyed    l.y    two 


YELLOW   FEVER.  169 

nonimmune  "controls,"  who,  protected  only  by  a  wire-screen  parti- 
tion, had  been  present  at  each  of  the  subject's  visits  and  who  under 
the  same  conditions  of  security  against  the  bites  of  the  infected  mos- 
quitoes continued  to  sleep  in  and  breathe  the  com  mom  atmosphere 
of  this  room  for  yet  18  nights. 

To  the  positive  cases  contained  in  Table  II,  which  were  produced  at 
Camp)  Lazear,  we  are  now  able  to  add  4  other  cases  of  yellow  fever 
occasioned  by  the  bites  of  infected  mosquitoes,  thus  making  a  total  of 
14  cases,  in  each  of  which  happily  recovery  followed. 

A  very  important  point  brought  out  by  these  observations  is  that 
an  interval  of  about  12  days  or  more  after  contamination  appears  to 
be  necessary  before  the  infected  Stegomyia  is  capable  of  conveying 
the  disease  to  a  susceptible  individual.  Repeated  experiments  made 
with  insects  which  had  bitten  yellow  fever  patients  2  to  10  days  pre- 
viously were  always  negative,  although  these  same  insects  were 
proven  capable  of  conveying  the  disease  after  having  been  kept  until 
17  to  24  days  had  elapsed.  Our  observations  (14)  further  demonstrate 
that  mosquitoes  that  have  been  kept  for  periods  varying  from  39  to 
57  days  after  contamination  are  still  capable  of  conveying  the  disease, 
and  further  that  infected  Stegomyia  may  survive  for  a  period  of  at 
least  71  days.  This  will  explain  how  the  contagion  of  yellow  fever 
may  cling  to  a  building,  although  it  has  been  vacated  for  a  period  of 
two  or  more  months. 

Bearing  in  mind  that  the  observations  made  by  means  of  blood 
injections  (Table  I)  were  only  undertaken  after  we  had  succeeded  in 
demonstrating  that  the  disease  could  be  conveyed  by  the  bites  of 
infected  Stegomyia,  it  will  be  seen  that  our  study  of  the  method  of 
propagation  of  yellow  fever,  at  Camp  Lazear,  sufficed  to  prove  very 
definitely  that,  while  the  natural  mode  of  transmission  of  this  disease 
is  through  the  bites  of  infected  mosquitoes,  yellow  fever  may  also  be 
conveyed,  like  malarial  fever,  by  the  injection  of  a  small  quantity  of 
blood  taken  from  the  veins  of  an  individual  suffering  with  this  disease. 

Per  contra,  our  observations  show  that,  notwithstanding  the  com- 
mon belief  in  this  mode  of  transmission,  yellow  fever  can  not  be 
induced  in  the  nonimmune  individual  even  by  the  most  intimate  con- 
tact with  contaminated  articles  of  clothing  and  bedding. 

Although  the  investigations  made  at  Camp  Lazear  were  only  con- 
cluded one  year  ago,  already  confirmatory  evidence  of  the  strongest 
character  has  been  furnished  in  a  series  of  experiments  carried  out  by 
Guiteras  (15)  at  the  inoculation  station  of  the  sanitary  department 
of  Habana. 

I  may  be  pardoned  for  quoting  the  paragraph  with  which  Guiteras 
begins  his  contribution.  He  says :  ' l  The  favorable  results  obtained  by 
the  United  States  Army  commission  in  their  experiments  with  yellow 
fever,  the  continued  series  of  mild  cases  resulting  from  these  experi- 
ments without  a  death,  suggested  very  naturally  the  continuation  of 
their  work  on  a  larger  scale ;  not  with  a  view  to  control  or  confirm  the 
conclusions  of  the  commission,  for  anyone  who  had  followed  their 
work  with  unprejudiced  attention  must  have  concluded  that  their 
solution  of  the  problem  of  the  etiology  of  yellow  fever  was  final;  but 
rather  in  the  hope  of  propagating  the  disease  in  a  controllable  form, 
and  securing  amongst  the  recently  arrived  immigrants  immuniza- 
tion, with  the  minimum  amount  of  danger  to  themselves  and  the 
community." 


170 


YELLOW    FEVER. 


Of  a  total  of  4'J  individual-  inoculated  by  (iuiteras  •_>,">  were  rejected 
by  him   by    D  .\\i\£  been   bitten   by   in^eeis   that    had   been 

apohed  to  cases  of  fever  about  which  the  diai:  -in  doubt.      The 

following  table,  therefore,  only  includes  17  per-ons  \\lio  were  bitten 
by  Stegomyva  that  had  previously  foil  on  unmistakable  ca><^  (•('  \  ellow 
fever  at  im«T\aU  of  l  l  -re  being  applied  to  the  non- 

immune  subject. 

TABLE   111 


No. 
of 

DftU  of  (nor- 
ulaiion. 

Uode  of  inoculation. 

Result. 

Feb.  23.1901 
Aug.     4.  1901 

Mosauito... 

Positive. 

3  days,  10  hours. 

do 
Aug.     7.1901 
A.;*     ^  LOOJ 
do 

do. 
do 
do. 

do  

i       •     • 
..     .do  

-.5  hours. 

•i  '1  i\  •>•   '.',  hours 

Aug. 

\ut      '.«  'r«'l 

..'.do.... 

Posit 

Aug    10.1901 

do 

10 
11 

...do. 
do 

do 
do 

.do 

\Ug    13  1901 

do 

Positive 

3  day*  19  hours 

13 

do 

do 

Negative 

14 

\ug    14  1901 

do 

15 

do. 

do 

do 

16 

Aug.  22.1901 
Aug.  24,1901 

do 
do.... 

Sdaya. 

A  more  complete  confirmation  of  the  results  ol>tain<'d    h\    the 
American  commission  could  not  be  furnished  than  the  data  eontained 
in  the  foregoing  table,  since  they  show  that  of  17  individuals  who 
were  bitten  by  infected  Stegoniyia  fasciata ,  8  (47  per  cent )  devrl 
the  disease.     Most  unfortunately,  in  three  of  these  cas<  rave 

symptoms  ensued,  such  as  Mark  vomit  and  suppression  of  the  urine, 
which  eventuated  in  the  death  of  the  patients.  I  may  add  that  in  the 
hands  of  Guiteras  fomites  failed  to  exert  any  effect  on  nonimmun 

Whether  other  species  of  mosquitoes  than  Stegomyia  are  capable  <>f 
conveying  the  parasite  of  yellow  fever  has  not  as  yet  been  determined 
by  the  commission;  nor  have  we  been  able  to  ascertain  whether  the 
parasite  passes  from  the  mother  insect  to  daughter  Insects*  The 
experiments  which  we  have  thus  far  been  able  to  make  for  the  pin 
of  determining  these  important  points,  although  negative,  have  hern 
too  few  in  number  to  warrant  any  definite  expression  of  opinion. 

THE  PREVENTION  OF  YELLOW  FEVER. 

The  definite  determination  of  the  way  in  which  yellow  fever  is 
transmitted  from  the  sick  to  the  well  furnishes  a  solution  at  h: 
that  much  vexed  problem  of  how  to  prevent  the  spread  of  the  di- 
Even  in  the  absence  of  more  definite  kmmled^e  eonrernii  ••rific 

agent— knowledge  greatly  to  be  de>h-cd  from  the  scientific  stand- 
point— we  are  now  able,  as  sanitarians,  to  direct  our  efforts  alon- 
tain  well-defined  lines,  with  a  fcelim:  :ity  heretofore  unki> 

From  the  point  of  view  of  prevention  the  situation  may  be  briefly 
summed  up  in  the  following  conclusion,  which  v.  .-nted  by  the 

American  Army  commission  to  the  Pan-American  (  ..f  moo.1 


/.-«•  eft, 


YELLOW   FEVER.  171 

viz,  "The  spread  of  yellow  fever  can  be  most  effectually  controlled  by 
measures  directed  to  the  destruction  of  mosquitoes  and  the  protection 
of  the  sick  against  the  bites  of  these  insects." 

This  conclusion  was  the  logical  outcome  of  the  observations  that 
had  been  made  by  the  commission  at  its  experimental  station  near 
Quemados,  Cuba'. 

The  importance  of  the  discovery  that  yellow  fever  is  transmitted  by 
the  bite  of  a  certain  species  of  mosquito  did  not  fail  to  attract  the 
prompt  attention  of  the  military  governor  of  the  island  of  Cuba, 
himself  a  physician  and  formerly  a  distinguished  member  of  the 
Medical  Department  of  the  United  States  Army.  By  his  direction 
the  theory  was  at  once  subjected  to  a  practical  test  in  the  city  of 
Habana,  in  which  city  yellow  fever  had  not  failed  to  make  its  yearly 
appearance  during  the  past  140  years. 

Under  the  efficient  management  of  the  chief  sanitary  officer, 
Surg.  Maj.  Wm.  C.  Gprgas,  United  States  Army,  the  sanitary  regula- 
tions were  so  far  modified  as  to  require  that  every  patient  having  yel- 
low fever  should  not  only  be  quarantined,  but  that  his  room  should  be 
promptly  protected  with  wire  screens,  so  as  to  prevent  the  possibility 
of  mosquitoes  becoming  infected  by  sucking  the  blood  of  the  patient. 
As  a  second  important  measure,  a  systematic  destruction  of  all  mos- 
quitoes in  other  rooms  of  the  patient's  house,  as  well  as  in  adjoining 
houses,  was  at  once  begun,  the  fumes  of  pyreihrum  being  relied  upon 
to  stupify  the  insects,  after  which  they  were  carefully  swept  up  and 
burned.  In  other  words,  Surg.  Maj.  Gorgas  relying  upon  the  well- 
known  slow  progress  of  yellow  fever  sought  to  destroy  all  mosquitoes, 
infected  or  noninfectecl,  within  a  given  radius  of  each  case,  while  at  the 
same  time  he  effectually  excluded  all  mosquitoes  from  access  to  the 
sick.  If  a  secondary  case  occurred,  the  same  hygienic  measures 
were  vigorously  enforced  along  the  lines  above  indicated. 

As  an  illustration  of  what  has  been  accomplished  by  these  newer 
sanitary  regulations,  I  may  state  that  counting  from  the  date  when 
they  were  put  into  force — viz,  February  15,  1901 — Habana  was  freed 
from  yellow  fever  within  90  days;  so  that  from  May  7  to  July  1— 
a  period  of  54  days — no  cases  occurred.  Notwithstanding  the  fact 
that  on  the  latter  date,  and  during  the  months  of  July,  August,  and 
September,  the  disease  was  repeatedly  reintroduced  into  Habana 
from  an  inland  town,  no  difficulty  was  encountered  in  promptly 
stamping  it  put  by  the  same  measures  of  sanitation  intelligently 
applied  both  in  the  city  of  Habana  as  well  as  in  the  town  of  Santiago 
de  las  Vegas,  whence  the  disease  was  being  brought  into  Havana. 

As  a  further  illustration  of  the  remarkable  sanitary  victory  accom- 
plished over  a  disease  whose  progress  we  had  heretofore  been  powerless 
to  arrest,  I  will  close  this  paper  by  inviting  the  reader's  attention,  first 
to  the  accompanying  Chart  I,  which  shows  the  average  monthly 
mortality  from  yellow  fever  in  Habana  for  the  20  years  1880-1899, 
inclusive,  and  also  the  mortality  by  month  for  the  years  1900  and 
1901.  I  will  then  ask  him  to  examine  Chart  II,  which  shows  the 
progress  of  yellow  fever  in  Habana  during  the  epidemic  year,  ending 
March  1,  1901,  when  the  sanitary  authorities  were  putting  forth  every 
effort  known  at  that  time  to  sanitary  science  in  order  to  control  the 
march  of  the  disease;  and  when  he  has  satisfied  himself  that  no  effect 
whatever  was  produced  upon  the  epidemic  of  that  year,  I  will  invite 
his  attention  to  Chart  III,  which  shows  the  occurrence  of  this  disease 


172 


YELLOW     KKVER. 
(11  MIT  I. 


Showing  monthly  mortality  from  yellowfever  in  the  city  of  Havana,  for  the  twenty  years, 


1900-1901. 


Dec. 


Oct. 


-  June 


My- 

Jany. 


YELLOW   FEVER. 


173 


CHART  II. 

Cases  and  deaths  from  yellow  fever  in  the  city  of  Havana,  for  the  epidemic  year    March  1 
1900,  to  March  1,  1901  (by  month}. 


CHART  III. 

Cases  and  deaths  from  yellow  fever  in  the  city  of  Havana,  for  the  epidemic  year,  March  1, 
1901,  to  March  1,  1902  (by  month). 


1901 
~T 


J9M 


J&nttv  g 


SO 


•Cases. 


174  YK.I.I.OU 


in  Habana  for  the  epidemic  year  March  1.   l'M)i,  to  March  1.1 
during  which  year  Yellow  fever  was  fought   on  the  theory  that  the 
specific  agent  of  this  disease  is  transmitted  solely  hy  means  of  the 
bites  of  infected  mosquitoes.     By  carefully  comparing  the  figures 
both  as  to  deaths  and  cases  in  these  two  charts,  and  recalling  that 

between  the  \ears  1853  and  1900  there  have  hern  recorded  in  the  city 

iubana  3">.t».YJ  d«  in  \ellow  fever,  he  \\ill  then  he  ahle  to 

more  clearly  appreciate   the   \alue  of  the  work   mvomplishnl    hy   the 

American  Army  commission. 

BIBUOGRAI  IM 

(1)  Report  on  th««  Kii..  !..-:>•  am)  rr«-\.'ini.-i 

(2)  LA  Fiebre  Amarilla.     (  ..nf.  r.  n.  ia  <lada  en  la  Universidad  de  Mmit.-vi.i. 
10Juniol897.    Reprint 

(3)  Bacteriological  Study  in  th<-  Kticlc-ry  ..f   y,.||,,\v    I-'.-V«T.     \,-n-    York    M 
Journal,  Jan.  28,  1899  pp.  109  111 

(4)  Summary  of  Pathologic  and  Bacteriologie  Work,  at  Isolation,  N«- 
nal  of  the  American  Medical  Association,  April  16,  1898,  pp.  884-888. 

(5)  Tin-  Ktiolo-y  <>f  Y<-llo\v  Fcv.-r.     Al.stractof  Report,  <fcr.     N.   Y.  Med.  .Innnuil. 
August  26,  1899,  pp.  299-302. 

(6)  Report  upon  Bacteriological   Investigations  in   Yellow   Pew,    Hi.     M 
News,  N.  Y.,  February  10  and  17,  1900. 


(7)  KevistacT  Igiene  e  Sanita  I'tiMim.  \i.  No.  IH.  July,  1900,  pj' 

(8)  La  Ba<  illc  Icterolde  «M  Sa  T«-xiin  •.     Archives  de  Medicine  Experimental*  <(:< 
1899,  pp.  378-398. 

(9)  Nota  para  Servir  al  estudio  bacteriologico  de  la  Fiebre  Amarilla.    Gaceta  Medico 
de  Mexico,  xxxvi,  1899,  pp.  218-230. 

(10)  The  Etiology  of  Yellow  Fever.    A  Preliminary  Note.    The  Philadelphia  Med. 
Journal.  ()<-i.,l».-r  'J7.  1900. 

(11)  Yellow  Fever.     Buck's  Reference  Hand-book  of  the  Medical  Sciences,  Vol.  vni. 
1889,  p.  48. 

(12)  The  Etiology  of  Yellow  Fever.    A  Supplementary  Note.    American  Mcd 
Vat  in.  No.  8,  February  22,  1902,  pp.  301-305. 

(13)  The  Etiology  of  Yellow  Fever.    An  Additional  Note.     Jo 
Medical  Association,  February  16,  1901. 

(14)  Experimental  Yellow   Fever.     Transactions  of  the  Association  of  American 
Physicians,  Vol.  xvi,  1901. 

(15)  Experimental  Yellow  Fever  at  the  Inoculation  Station  of  tin-  Sanitary  1  •Apart- 
ment of  Havana.    American  Medicine.  Vol.  n,  No.  21,  1901,  pp.  809-817. 


OR.  JAMES  CARROLL. 


PART  III— THE  PUBLICATIONS  OF  JAMES  CARROLL,  ASSISTANT  SUR- 
GEON, UNITED  STATES  ARMY,  IN  REGARD  TO  YELLOW  FEVER, 

[Published  after  the  death  of  Maj.  Walter  Reed.] 


CHAPTER  1. 
THE  TRANSMISSION  OF  YELLOW  FEVER.1 

By  JAMES  CAEROLL,  M.  D., 
Assistant  Surgeon,  United  States  Army. 

[Read  at  the  forty-fourth  session  of  the  American  Medical  Association,  in  the  section  on  practice  of  medi- 
cine, and  approved  for  publication  by  the  executive  committee:  Drs.  J.  M.  Anders,  Frank  A  Jones  and 
W.  S.  Thayer.] 

Several  American  observers  have  noted  that  during  the  yellow 
fever  outbreaks  mosquitoes  were  very  numerous,  among  them 
Rush(l),at  Philadelphia  in  1797;  Dr.  Weightman(2),  of  the  United 
States  Army,  at  St.  Augustine,  Fla.,  in  1839;  Dr.  Wood (3),  at  Center- 
ville,  Miss.,  in  1853.  Dr.  E.  H.  Barton (3)  states  "that  at  Clinton, 
La.,  in  1853,  mosquitoes  were  uncommonly  numerous  night  and  day." 
At  Trinity,  La.,  in  the  same  year,  when  sawdust  was  used  to  fill 
up  low  places  in  the  streets,  the  disease  was  not  propagated,  though 
many  cases  were  brought  there  and  no  precautions  were  used  (3). 
It  is  hardly  necessary  to  note  what  the  effect  of  this  obliteration  of 
puddles  would  be  on  the  development  of  mosquitoes.  Dr.  Beyren- 
heidt(3),  of  Biloxi,  Miss.,  in  reporting  a  severe  epidemic  at  that  place 
in  1853,  during  which  533  cases  and  111  deaths  occurred  in  a  popula- 
tion of  5,520,  makes  the  interesting  statement  that  "  mosquitoes 
and  fleas  were  very  abundant."  Dr.  Bennett  Dowler  strongly 
urged  drainage  of  the  city  of  New  Orleans,  and  spoke  of  the  city  and 
its  environs  as  "  mosquito  lands  "(4).  La  Roche  (5)  states  that  in 
1793,  during  the  epidemic  in  Philadelphia,  "the  narrow  streets  and 
alleys  near  the  wharves,  as,  indeed,  in  many  other  parts,  were  in  a 
foul  state,  and  the  gutters  almost  everywhere  sadly  neglected."  In 
1794  Rush  and  others  ascribed  the  fever  to  exhalations  from  wharves, 
neglected  gutters,  and  stagnant  ponds(5).  In  1797,  during  another 
outbreak  in  Philadelphia,  the  condition  was  practically  the  same; 
the  Academy  of  Medicine  called  the  attention  of  the  governor  to 
the  putrid  exhalations  from  the  gutters,  streets,  ponds,  and  marshy 
grounds  of  the  neighborhood  of  the  city  (5).  While  high  temperature, 
low  altitude,  and  the  presence  of  standing  water  are  the  conditions 
most  favorable  to  the  development  of  a  yellow  fever  epidemic,  there 
are  numerous  instances  on  record  where  the  disease  after  introduc- 
tion spread  from  house  to  house  throughout  the  town  in  places 
where  the  general  conditions  of  sanitation  and  drainage  were  good. 
This  is  now  explained  by  the  habits  of  the  mosquito  (Stegomyia 
fasciata),  which  Dreeds  in  standing  water,  in  houses  as  well  as  out  of 

i  Journal  of  the  American  Medical  Association,  May  23, 1903. 

175 


176  YELLOW 


doors.  As  a  general  rule,  in  ports  where  yellow  fever  epidemics  first 
appear,  the  conditions  arc  known  to  be  favorable  for  the  dovelop- 
incnt  of  enormous  numbers  of  mosquitoes. 

A  very  interesting  observation  \\as  mad.'  in  ix:w  in  South  Africa 
by  William  Ferguson.  then  a  surgeon  in  the  South  African  corps,  in 
regard  to  the  extension  of  yellow  fever  from  Sierra  when1  it 

had  been  brought  on  vessels  from  tho  West  Indies)  to  (iambia. 
Goree,  and  Ascension,  the  subsequent  ports  of  arrival  of  some  of 
these  infected  vessels.  After  mentioning  an  unusually  heavy  accu- 
mulation of  mud  and  filth  in  a  pit  at  Ascension,  which  was  -aid  to 
have  been  the  cause  of  the  fever  oceurring  after  an  unusually  heavy 
fall  of  rain,  he  makes  the  following  statement: 

(6)  It  will  be  observed  that  at  AN  <>c.  and  at  Gambia  a  •  hrcc 

or  four  weeks  always  elapsed  betwixt  the  landing  of  the  sick  ami  tin-  ••j.i.irniie  ..ui- 
breaking  of  the  disease  among  the  Dopulation,  a  degree  of  uniformity  worthy  of  remark 
\\  lu-ther  the  conclusions  at  wni<h  I  have  arrived  (mat  the  disease  was  earn 
places  on  infected  vessels)  be  mistaken  or  not. 

These  outbreaks   were   accompanied   by   black    vomit    and 
undoubtedly  yellow  fever  of  imported  origin. 

.lust  60  years  later  Carter  (7)  made  a  similar  observation  in  the 
United  States,  shortening  the  period  slightly  and  givinir  cases  and 
data.  In  a  later  paper  (8)  he  de-senates  the  interval  hot  ween  pri- 
mary and  secondary  cases  the  period  of  "extrinsic  incubation." 

The  known  facts  regarding  tne  apparent  noncontagiousness  of  the 
disease,  the  peculiar  manner  in  winch  it  has  been  seen  to  pass  from 
one  house  to  another  without  intercommunication  of  the  inhahh  , 
and  the  numerous  points  of  resemblance  between  yellow  lever   and 
malaria,  led  us  to  expect  results  from  mosquito  inoculations  in  \  el  low 
fever.     After  satisfying  ourselves  that  B.  icteroides  (Sanardli 
not  to  be  considered,  Drs.  Reed,  Lazear,  and  myself,  in  consultation. 
decided  that  the  mosquito  theory  had  many  facts  to  support   ii 
could  be  promptly  decided  one  way  or  the  other.     This  lead-  iu 
consideration  of  the  mosquito  theory  of  Finlay. 

At  the  session  of  the  Royal  Academy  of  Sciences,  Habana.  Ai: 
14,  1881,  Finlay  first  gave  to  the  world  his  memorable  theory  of  the 
transmission  of  yellow  fever   by  the  mosquito,  and    reported 
experiments,  which  are  included  in  the  accompanying  table,  compris- 
ing all  of  Finlay's  and  Delgado's  positive  cases  piiblisned  in  1  v  1 

Finlay  believed  (10)  that  the  transfer  of  the  specific  agent  of  the 
disease  from  patient  to  nonimmune  was  effected  mechanically  by  t  he 
insect's  proboscis  (14)  and   that  the  infection  would    be  convc 
immediately  if  the  insect  chanced  to  bite  a  susceptible  person  a  few 
moments  alter  feeding  on  a  patient  in  the  proper  stage  of  the  dis- 
ease. (11)      He  also  thought  that  the  graver  forms  of  yellow  fever 
might  be  produced  by  the  bite  of  CuLex  pungens,  because  the  i 
ingested  a  larger  amount  of  blood  than  stegomyia,  and  consequently 
a  greater  quantity  of  the  virus  would  be  retained  on  its  piob 
(stylet).  (11)      He  ventured  the  opinion  that  yellow  foyer  Wi 
of  eruptive  fever,  and  that  the  seat  of  the  eruption  was  the  on  dot  ! 
lining  of  the  blood  voxels,  and  that  the  mosquito  nicked  up  t  he  inocii-- 
lable  material  f  rom  the  interior  of  the  blood  vessef>  on  its  biting  appa- 
ratus  and  transferred  the  same  to  the  interior  of  the  vessels  of  the  per- 
son subsequently  bitten. 


YELLOW   FEVER. 


177 


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er 
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o          o          o 

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a 


IN  »o      oo 


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£2  ^^  ^  ^ 


CO  CC(N       (M 


when  the 
was  bitte 


IS        •<        ^ 


Date  of  contam 
of  mosquit 


3333       33 


79965°— S.  Doc.  822,  61- 


178  VEB. 

In  a  later  paper  he  assumes  that  the  picking  up  of  those  germs  by  tho 
proboscis  of  the  moMjuito  is  selective,  because  there  i^  nothing  in  prove 
that  other  inoculable  diseases  have  I  D  BO  ( i an-mitted.  From 

four  culture  experiment*-,  in  each  of  which  the  head  and  the  pro- 
boscis of  a  mosquito  W6I6 dropped  into  a  bouillon  tube,  he  infers  that 
the  head  and  the  pro)..-. -U  ot  t:  .uito  possess  bactericidal 

properties  for  ordinary  bacteria  and  fungi  \\ith  the  exception 
08,  \vliich  was  subset | uen tly  1 1- >  claimed  to  be  the  specific  a 
of  the  disease.  (!-".)     The  sting  of  the  mosmiito  b  suggested  as  the 
"intermediate  host"  necessary  for  some  pnase  of  development  of 
disease  germs.  (14) 

As  late  as  1899  Kinlay  mentions  the  isolation  of  the  tetracoccus  from 
culture  media  into  which  the  heads  and  nroboscides  of  contamin 
mosquitoes  had  boon  dropped,  as  one  of  t ne  three  result-  of  his  e  \peii- 
ments  on  yellow  fever  mosquitoes. 

In  a  paper  (13)  published  in  1895  he  announced  some  very  inte 
ing  results  obtained  with  the  "tetracoccus."     A  number  of  rabbits 
were  inoculated  in  traperi  tone  ally  with  cultures  in  bouillon;  one  of 
these  cultures  had  been  obtained'from  the  head  and  the  proboscis 
mosquito  bv  placing  them  in  a  tube  of  bouillon  five  days  after  the 
insect  had  bitten  a  yellow-fever  patient;   the  others  came  from  the 
finger  blood  and  milk  of  yellow-fever  patients.     All  of  the  rabbits 
died;  some  of  them  showed  infarcts  of  the  kidneys,  lungs,  and  liver. 
A  rabbit  obtained  from  the  count  rv  was  placed  in  the  stable  where 
some  of  the  other  rabbits  had  been  kept,  and  at  the  end  of  eight  days 
it  was  found  dead.     The  tetracoccus  was  obtained  from  its  he; 
blood. 

Eleven  days  after  the  rabbits  had  been  removed  from  the  house 
(the  stable  is  usually  a  part  of  the  house  in  Habana)  a  Spanish  wet 
nurse  came  to  spend  some  time  there  and  on  the  third  day  following 
her  arrival  she  was  attacked  with  yellow  fever.  Mosquitoes  had  been 
unusually  abundant  in  the  house  during  the  whole  time  the  inocu- 
lated rabbits  had  been  kept  in  it,  and  we  are  asked  to  keep  this  in 
mind  in  view  of  the  possible  transmission  of  the  disease  from  animals 
to  man.  We  are  told  that  the  blood  from  the  finger  of  this  woman  on 
the  third  day  of  her  illness  gave  the  "pale  yellow  tetra<  and 

the  milk  from  her  breast  gave  a  "white  tetracoccus,"  which  pi 
fatal  to  a  rabbit  in  15  days.  (13) 

While  reading  the  accounts  of  these  experiments  one  is  coiiMantly 
reminded  of  the  pathogenic  staphylococci.     It  is  strongly  - 
(13)  that  the  rabbits  died  of  yellow  fever,  and  it  is  asserted  that  the 
experiments  justified  the  assumption  that  the  tetracoccus  wa>  the 
"specific  germ  of  yellow  fever." 

The  statement  is  also  made  in  this  paper  that  of  100  presumably 
susceptible  person-  who  had  received  the  mosquito  inoculation  during 
the  14  years  previous,  only  3  had  subsequently  died  of  vellow  fever. 
(13) 

I  have  been  unable  to  find  records  of  these  100  cases  in  the  library 
of  the  Surgeon  General's  Office,  and  submit  those  of  which  the  data 
area*  ce^i  Me  tome.     As  these  include  the  cases  on  which  Dr.  Fin! 
claim  is  based  they  will  suffice  for  the  purpose.    The  54  negative  cases 
are  omitted. 


YELLOW   FEVEE.  179 

Case  3  was  bitten  by  a  mosguito  that  had  been  fed  on  bloody 
excrement  from  another  mosquito  that  had  been  found  inside  the 
mosquito  net  of  a  fatal  case.  The  material  was  allowed  to  dry  for 
27  days  in  the  test  tube  and  was  then  moistened  with  a  little  sugar 
and  water  to  prepare  it  for  feeding.  (15)  There  is  a  marked  difference 
between  the  method  of  procedure  herein  described  and  that  given  in 
1901,  (16)  when  Dr.  Finlay  said: 

I  applied  a  nocturnal  mosquito  and  allowed  it  to  fill  itself  from  a  case  of  yellow  fever. 
After  pricking  the  side  of  the  insect's  abdomen  I  mixed  the  blood  which  escaped 
with  a  drop  of  sterilized  sirup  and  fed  with  it  a  fresh  culex  mosquito,  and  finally 
applied  the  latter  to  a  third  soldier  (July  29).  Two  days  later,  July  31,  the  soldier 
went  to  the  hospital  with  a  fever  which  was  also  recorded  as  "abortive  yellow  fever." 

This  case  (L.  G.  P.)  was  omitted  from  the  paper  published  in  1881, 
as  stated,  but  was  included  in  1891  in  the  report  from  which  the  cases 
here  recorded  are  taken. 

Case  4  is  further  discussed  in  English  in  a  footnote  on  page  368  of 
the  Kevista  de  la  Asociacion  Medico-Farmaceutica,  Haoana,  Feb- 
ruary, 1902.  (History  of  illness  vague.  Did  not  go  to  bed  or  report 
himself  sick.)  The  first  5  cases  were  newly  arrived  soldiers,  stationed 
at  Cabanas  and  who  were  brought  to  the  city  of  Habana  for  exami- 
nation once  in  every  5  days. 

Case  9  is  cited  by  Finlay  (17)  in  refutation  of  pur  conclusion  (18) 
that  the  mosquito  is  not  capable  of  infecting  until  about  12  days  or 
more  have  elapsed  after  it  has  bitten  the  patient. 

Case  55  was  a  Spaniard,  newly  arrived,  who  lived  at  a  country 
residence.  At  both  attempts  to  inoculate  him  the  mosquitoes  failed 
to  bite;  nevertheless  he  was  taken  sick  August  26.  Another  non- 
immune  who  occupied  an  adjoining  room  was  taken  sick  with  similar 
symptoms,  a  few  days  later.  No  further  comment  is  necessary, 
except  that  the  cases  of  the  Army  commission  and  of  Dr.  Guiteras 
were  kept  under  close  observation  and  strict  control.  Nearly  all  of 
Dr.  Finlay 's  cases  were  exposed  to  infection  in  the  city  of  Habana. 
Only  four  of  them  come  within  the  recognized  periods  of  incubation, 
viz,  Nos.  2,  3,  4,  and  66.  The  first  three  of  these  were  inoculated  in 
Habana  in  July,  1881,  during  which  month  there  were  90  deaths 
from  yellow  fever  in  that  city  alone.  The  last  was  inoculated  in 
August,  1890.  In  that  month  60  deaths  from  yellow  fever  are 
recorded  for  the  city  of  Habana. 

Finlay  has  published  a  great  many  conjectures  and  speculations 
in  regard  to  yellow-fever  transmission.  Some  of  these,  such  as  the 
belief  that  the  disease  was  transmitted  by  the  mosquito,  have  been 
proven  by  our  work,  but  not  in  accordance  with  his  ideas.  I  can 
nnd  no  evidence  that  he  has  produced  a  single  case  of  yellow  fever 
by  his  inoculations.  In  the  first  place  the  mosquito  is  incapable  of 
transmitting  the  disease  in  so  short  a  period  as  2  to  5  days  after 
biting  the  patient.  In  the  second  place  7  days  must  be  placed  as  the 
extreme  limit  of  incubation  in  the  human  being.  Our  longest  period 
was  between  5  and  6  days.  Finlay  conveniently  puts  the  ordinary 
limit  of  yellow-fever  incubation  between  5  and  22  days.  (14)  The 
efficiency  of  the  5-day  quarantine  regulation  proves  that  incubation 
in  man  certainly  does  not  extend  over  6  days,  or  7  at  the  extreme, 
and  in  the  30  experimental  cases  recorded  by  ourselves  and  Guiteras 
the  former  period  has  never  been  exceeded. 


180  YELLOW   FEN 

TABLE  2.— Negative  mosquito  inoculations  of  the  Army  commission. 


and  number  of  pe- 

Dayofdteeaw. 

tamo* 

qilito 

rooa 

tan  '.' 

Dateofappli- 
,  tttoool 

mosquito. 

NumUT 
...'  DM* 

qattoai 

Remarks, 

8 
9 

10 

11 

12 

13 

14 
15 

M 

17 
18 
19 
20 
21 
22 

MiM   1 

Seventh 

***'! 

6 
6 
8 

in 

6 

4 
2 
3 
6 
11 
6 
9 
14 

a 
u 

13 
10 
13 
16 
12 
12 
15 
18 
4 
11 
»22 

Aug.  11,1900 
....do  
Aug.  12,1901 

Aug.  14.1901 
log.  10,1901 

Aug.  19,1901 
Aug.  25,1901 

Nov.  20,1901 

Nov.  23,1901 

-••i,  1901 

Nov.  29,1901 

Nov.  28.1901 
-".1,1901 
Dec.     2,  1901 
Nov.  26,  1901 

Dec.     2,  1901 
Dec.   17.1901 
Dec.  24.1901 
Jan.    25,1901 

2 
1 

1 

1 
1 

1 
2 
1 

1 
2 
14 
7 
12 

Negative. 

Do. 
Do. 

Do. 

Negative;  p-M-tition. 

Do. 
Do. 

Do. 

Do. 
Do. 
Do. 
Do. 

Verjrmild. 

do. 
do. 
do 

iiiil 

Severe.  1 

Bemad 

i   ;••• 

I  1  •:  il    1 

9aoood 

"     . 

:  :• 

Bnood 

Third 

do 

do 

do 

Fifth...  , 

....do. 

Third. 
...do... 

do 

Fifth 

Moderate.  1  .  . 
i  Well  marked,  1... 

Third  

Second. 

(Moderate,  1  . 
1  Well  marked,  1. 

Third  

S'TOll'l 

Severe,  1 

do 

do  
/....do  
(Fatal  1 

do 
do 
Third 

Well  marked,  1  

do. 

do  
do  
Mild.l  
do 

do  
do  
First  
do 

V«ry  mild 

Eighth  hour.. 

>82«F. 

NOTE.— The  subjects  of  Experiments  Nos.  10, 11, 12, 13, 14, 15, 16, 17, 18, 19,  20,  and  21  were  prov. 
susceptible  by  subsequent  experimental  infection.    No.  22  declined  a  second  test.    In  Experiments  20  and 
21  the  same  set  of  insects  and  the  same  subject  were  used.    Four  of  these  insects  infected  this  man  six  days 
later,  on  December  30, 1900. 

In  a  letter  of  August  20,  1901,  Dr.  Finlay  (19)  states  he  was  con- 
vinced that  extension  of  the  interval  between  the  application  of  the 
mosauito  to  the  patient,  and  subsequently  to  the  nonimmune.  would 
develop  a  severe  attack,  such  as  he  was  anxious  to  avoid.  One  ran 
sympathize  with  the  humane  feeling  that  prompted  him  t<>  forego 
positive  proof  of  his  theory  rather  than  run  the  risk  of  produei 
severe  attack,  but  it  is  a  fact  that  on  August  22,  1901 .  two  days  Inter 
than  the  date  of  that  letter,  I  saw  Dr.  Finlay  apply  to  a  nonimmune 
two  mosquitoes  that  had  been  kept  34  days  after  contamination. 

I  have  been  impelled  to  look  .up  the  literature  of  this  Mil. 
because  I  have  seen  several  times  of  late  the.  statement  of  Dr.  I  inlay 
that  the  Army  Yellow  Fever  Commission  has  tacitly  ignored  his  ri^ht 
of  priority.   (21)     It  is  too  late,  after  facts  have  been  prov  -d   and 
recorded  by  others,  to  claim  priority  mile-,  one  <  an  point  to  un 
takable  evidence,  in  print,  as  proof  that  the  facts  have  been  den 
strated   and   duly  reported.     In   our   preliminary   report    (J_     Dr. 
Finlay  has  been  given  due  credit  for  priority  in  advancing  and  advo- 
cating the  mosquito  theory.     Nothing  more  is  due  to  him.     He 
states  (21)  that  he  had  "many  years  ago  discovered  that  yellow 
fever  was  transmitted  by  mosquitoes,"  when  in  reality  he  .-imply 


YELLOW   FEVER.  181 

assumes  that  to  be  the  case,  and  the  facts  recorded  by  him  do  not 
sustain  his  claim.  (23)  He  further  states  (21)  that  his  own  work  had 
been  singularly  misrepresented  before  the  American  public,  and 
that  "  among  the  facts  and  conjectures  which  are  attributed  to  the 
recent  investigators  there  is  scarcely  one  which  had  not  been  asserted, 
demonstrated,  or  suggested  by  me,  as  the  result  of  my  personal  experi- 
ments and  observations."  One  can  only  express  admiration  for  this 
eminent  scientist's  persistent  adherence  to  his  theory,  but  the  unbiased 
observer,  after  a  perusal  of  his  numerous  writings,  must  agree  with 
us  that  while  he  asserted  and  suggested  everything  that  intelligent 
reasoning  and  profound  knowledge  could  suggest,  he  failed  to  pro- 
duce a  single  case  of  the  disease.  Our  results  have  been  confirmed 
by  Guiteras  with  eight  cases  and  three  deaths;  (24)  Dr.  Finlay's 
assumed  results  have  never  been  confirmed  by  a  single  investigator. 
In  our  "  Additional  note"  (25)  we  report  among  other  instances  one 
in  which  the  bites  of  14  insects,  applied  4  days  after  contamination, 
failed  to  infect,  and  the  7  remaining  alive  failed  also  to  infect  1 1  days 
after  contamination,  but  on  the  seventeenth  day  following  contamina- 
tion the  bites  of  4  of  the  same  insects  produced  an  attack  of  yellow 
fever  in  "the  same  individual."  During  the  whole  of  this  time  these 
insects  had  been  kept  in  a  heated  room  at  an  average  temperature  of 
82°  F.  If,  as  is  claimed  by  Finlay,  (26)  protection  is  conferred  by 
one  or  two  bites  of  "recently  contaminated" — two  to  five  days  (19)— 
mosquitoes,  this  individual,  who  had  received  21  bites  from  recently 
contaminated  insects,  should  have  been  able  to  resist  the  bites  of  4 
of  the  same  insects  6  and  13  days  later.  Should  one  accept  Finlay's 
extension  of  the  incubation  period  to  22  days  infection  might  then 
be  erroneously  attributed  to  the  bites  inflicted  13  days  before  the 
onset  of  fever. 

^  The  Army  board  worked  on  an  entirely  different  hypothesis  from 
Finlay,  who  believed  that  the  infecting  agent  was  retained  on  the 
biting  parts  of  the  mosquito,  that  infection  was  direct,  and  no  interval 
was  necessary.  The  board  worked  on  the  hypothesis  that  the  specific 
agent  of  yellow  fever  was  probably  one  of  that  group  of  strict  parasites 
that  in  nature  necessarily  pass  through  two  distinct  and  alternating 
cycles  of  development,  one  within  the  body  of  a  vertebrate,  the  other 
within  a  blood-sucking  invertebrate  host.  Finlay  believed  that  the 
bite  of  a  single  insect  would  confer  a  mild  infection  and  multiple 
bites  a  severe  one.  In  my  own  case,  produced  by  the  bite  of  a  single 
insect,  a  fatal  result  was  looked  for  during  several  days.  Dr.  Lazear 
was  bitten  by  a  single  insect  and  died. (27)  I  became  so  firmly  con- 
vinced that  the  severity  of  an  attack  depended  on  the  susceptibility 
of  an  individual  rather  than  on  the  number  of  bites  sustained,  that 
on  October  9, 1901,  at  Habana,  I  purposely  applied  to  a  nonimmune 
8  mosquitoes  (all  I  had)  that  had  been  contaminated  18  days  before. 
The  attack  that  followed  was  a  mild  one ;  the  temperature  never 
reached  103°  F.,  and  dropped  to  normal  on  the  evening  of  the  fourth 
day.  (27) 

The  original  theory  of  Finlay  has  been  variously  modified  by  him 
from  time  to  time  to  meet  possible  contingencies.  He  now  evidently 
inclines  to  the  belief  that  development  of  the  germ  takes  place  in  the 
salivary  glands  of  the  infected  mosquito. (21) 


182 

TABLE  3. — Positive  mosquito  inoculations  of  the  Army  commission. 


No. 

3S52& 

-aar 

Daysofdl*. 

Ftjfcd 

tST 

Num. 

bard 

•::,.- 

gr 

:   •  0 
(••:>.  ;  «T- 

tttinfi 

;:,-..,•- 

Incubation. 

Severe,  l 

"•5 

1 

Bteood 

! 

1 

Aug.  27,1900 

3  day*  7  hours.... 

S.-N  ,-r... 

Mild.  8.. 

and 

2 

2 

Ojrr*r»»   7 

second. 

First      M«V 

1    2-16 

4 

Aug.  31,1900 

6  days  

Moderate. 

Fatal,  2 

and,  and 
third. 
Iwittd 

2-15 

3 

Severe,  l...-.  

Mild,  i 

do  
TbM 

1-19 

5 

Dec.     5,  1900 

3  days  10  boon... 

Pronounced. 

Fatal,! 

.do 

17 

Sever*,  2  

BOMBd  ;inil 

r      is 

4 

Moderate  1 

third. 
Third 

1   3 

4 

5  days  17  i 

Mi!<l. 

5 

Fatal  i 

Baooad 

19 

1 

Dec.     9,  1900 

3  days  12  hours. 

Do. 

....do  
Severe,  2  

Third  
Second  and 

H 

l       -i 

6 

Moderate,  1.. 

third. 
Third 

4 

Dec.   11,1900 

3  days  20  hours  .  .  . 

(   day. 

Severe,  1 

Second 

1-24 

7 

Well  marked,  2 

First. 

/  10-  5 

•      '  i:. 

Dec.   21,1900 

3  days  23  hours... 

P  ro  nou  need 

8 

Mild.  1 
.  ..do.. 

do  
.do    . 

1     4-'! 
17 

1  4 

Dec.  30,1900 

..  ..do... 

9 

Well  marked  1 

Third 

39 

1  3 

Jan.    19  1901 

4  days 

M.xi.Tiite 

10 

...do.. 

.      .do 

51 

'2 

Jan.    31,1901 

3  days  3  hours.. 

IfDd 

11 
12 

....do  
Fatal,  1  

do  
Second 

57 
16 

«2 
1  3 

Feb.     6.  1901 
Feb.     7,  1901 

3  days  6  hours  
2  days  22  hours.  .  . 

Moderate. 

13 

....do  

Ho 

Third  

QponnH 

1-53 

OOJ 

4 

Sept.  16,  1901 

3  days  

Scvi-re. 

14 

Severe,!  

do  

18 

8 

Oct.     9,  1901 

3  days  8  hours  

Mild. 

»82°  F. 

A  complete  proof  or  disproof  of  his  claim  of  positive  result-  id  his 
recorded  inoculations  could  easily  be  obtained  by  means  of  a  s< 
of  innocent  experiments.     It  is  interesting  to  note  that  at  ' 
time  when  this  distinguished  authority  is  in  position  to  ronlirm  the 
results  of  his  first  inoculations,  if  they  are  susceptible  of  coniii mation. 
he  takes  the  ground  that  inoculation  experiments  on  human  1>. 
in  Cuba  must  be  strictly  forbidden. (21) 

TABLE  4. — Positive  mosquito  inoculations  oj  Dr.  Guiteras. 


Character  of  at- 
tack and  num- 
ber paftatU 
bitten. 

Day  of  dis- 

Period  in 

mosquito. 

Number 
of  mos- 
quitoes 
used. 

DajfetoJ 
appltoa. 

tion  of 
UMaqai- 

toes. 

Inrutmtlon. 

Character  of  at  uuk. 

Firrt... 
Third 

"•"* 

19 

1 
4 

1901 
Feb.  23 
AUK.    8 

3  days,  10  hours... 
4  days  5  hours 

Pronounced. 

..do 

<io     . 

19 

4 

.<£... 

3  days,  3  hours  .  . 

Mild 

1 

do 

do 

20 

3 

Aug.    9 

5  days,  3  hours 

Fatal 

7 

do. 
do. 

I 

:::t 

24 
24 
24 

.!! 

1 
2 
3 
2 

Auc.  13 

AUK.   14 
AUK.  22 

3  days,  19  hours.. 
3  days,  21  hours.. 
5  days,  21  hours.. 

.5  'l.ivs 

MM. 
Fatal. 

M,Hl,-r:Up|v^v,.re. 
Srvi-rc 

i  Case  4  had  been  bitten  with  negative  result  10  days  previously  by  4  mosquitoes  5  days  after  they  had 
bitten  a  fatal  oaa»  in  the  third  day  of  the  disease.  See  Case  33  of  Cullerac?  table,  Aroer.Med.,  Nov.  23, 
1901,  p.  811. 


YELLOW    FEVER.  183 

It  is  unfortunate  that  Dr.  Finlay  in  his  numerous  contributions  to 
this  subject  very  seldom  gives  exact  references  that  would  enable  one 
to  compare  his  more  recent  assertions  with  his  former  statements. 
In  regard  to  his  expressed  opinion  that  the  great  merit  of  our  work 
consists  in  our  having  accurately  defined  the  danger  line,  beyond 
which  there  is  a  risk  of  producing  severe  or  fatal  experimental  cases 
when  nonimmunes  are  inoculated  with  mosquitoes  whose  contamina- 
tion is  more  than  10  days  old  (21),  I  desire  to  record  my  belief,  based 
on  experimental  observation  and  on  the  results  obtained  by  Guiteras, 
that  it  is  impossible  to  confer  protection  or  to  produce  infection  of 
any  grade,  with  an  insect  that  has  been  contaminated  less  than  a 
week,  and  that  inoculations  with  a  mosquito  contaminated  for  a 
shorter  period  will  be  absolutely  devoid  of  result.  The  accompany- 
ing tables,  compiled  from  our  and  Guiteras' s  cases,  afford  a  substantial 
basis  for  the  assertion.  I  deem  it  a  duty  to  the  service  to  which  I 
belong,  to  my  dead  colleagues  (Reed  and  Lazear)  and  to  the  profes- 
sion, to  state  the  facts  plainly  and  clearly.  I  do  not  expect  that  this 
paper  will  remain  unanswered;  nevertheless,  I  shall  decline  to  engage 
in  controversy  and  leave  the  final  determination  to  those  who  are 
competent  to  judge,  after  they  have  carefully  perused  the  publica- 
tions herein  referred  to. 

The  mosquito  theory  has  been  practically  demonstrated  by  the 
Army  commission  and  Dr.  Guiteras  in  two  series  comprising  22  cases 
in  all.  The  noncommunicability  of  the  disease  by  means  of  fomites 
has  been  a  matter  of  common  observation  in  certain  localities,  and 
has  also  been  demonstrated  practically  by  our  own  experiments  and 
those  of  Havard  and  his  associates.  Yellow  fever,  therefore,  is  not 
a  filth  disease,  in  the  strict  sense  of  the  term,  and  filthy  accumula- 
tions are  dangerous  in  this  connection  only  when  accompanied  by 
sufficient  moisture  to  breed  mosquitoes  under  favorable  conditions 
of  temperature.  Under  such  conditions  standing  water  is  a  source 
of  danger,  within  dwellings  or  without,  and  whether  dirty  or  clean, 
unless  it  be  kept  covered  or  is  changed  every  few  days.  Yellow  fever 
is  a  preventable  disease;  quarantine,  if  effective,  will  exclude  it,  but 
if  the  quarantine  be  evaded  and  cases  gain  entrance  to  a  city  the 
disease  can  be  absolutely  controlled  and  finally  exterminated  by 
measures  directed  against  the  mosquito  alone. 

Carter  (7)  has  well  shown  (8)  that  first  cases  are  not  dangerous 
until  after  the  lapse  of  a  number  of  days,  for,  in  his  experience,  persons 
in  direct  contact  with  them  for  a  few  days  only  never  developed  the 
disease  after  being  placed  in  quarantine.  This  applies  only  to  the 
first  cases  occurring  in  a  town  or  neighborhood.  He  found  that 
secondary  cases  did  not  appear  until  the  expiration  of  a  number  of 
days,  varying  from  11^  to  29,  the  average  being  18.  This  interval 
represents  the  time  necessary  for  the  mosquito,  after  biting  a 
patient,  to  become  capable  of  infecting,  plus  the  period  of  incubation 
in  the  person  bitten. 

The  greatest  obstacle  to  the  control  of  this  disease  is  the  failure  to 
recognize  the  first  cases  when  they  are  not  accompanied  by  black 
vomit.  Some  of  these  cases  are  so  mild  in  character  that  no  physi- 
cian would  dare  to  pronounce  them  yellow  fever  unless  he  knew  the 
disease  to  be  prevailing  at  the  time.  Susceptible  persons  visiting 
the  house  or  living  in  adjoining  houses  would  be  bitten  and  develop 
the  disease  in  near  or  distant  localities  several  weeks  later,  forming 


184  i>ow  FK\ 

secondary  foci  of  infection.  From  these  secondary  foci  tertiary  foci 
would  in  time  develop.  The  diagnosis  of  bilious  remittent  fever. 
dengue,  etc.,  would  serve  to  cover  the  earlier  cases  until  the  appear- 
ance of  black  vomit,  by  which  time  the  infection  would  :  .-me 
more  or  less  widely  disseminated.  Such  is  the  history  of  many 
outbreak 

The  number  of  mosauitoes  in   infested  districts  can  always  be 
appreciably  diminished  by  giving  attention  to  surface  drainage  and 
the  removal  of  standing  water.  n< »  matter  ho\v  small  t  he  (juantit y  or 
how  pure  the  quality  may  be.     Kain  jLrutteis  and  conduits  on  huild- 
.ings  should  be  kept  clear  and  free;   cisterns,  v\«-lU.  llu-h  tanks,  and 
Other  permanent    receptacles  for  water  should   be  kept    tightly  • 
ered  or  securely  screened;  privies  and  cesspools  should  be  cared  1'or; 
air  vents  to  cisterns  and  wefts  pro  tec  ted  by  screens,  and  water  should 
never  be  permitted  to  stand  in  any  vessel  or  receptacle  within  a 
building  longer  than  three  or  four  days.     Ditches  and  open  d< 
containing  water  should  be  frequently  ilushed;    old  cans,  <•• 
etc.,  should  be  removed  from  the  vicinity  of  duelling-:     p<»>ls  or 
ponds  should  be  stocked  with  iish  and  deepened  ai  the  margins  or 
treated  with  petroleum.    As  the  stegomvia  is  largely  a  house-dwelling 
and  a  house-^breedinir  in<ect,  these  and  other  similar  n<  wifl 

surely  diminish  their  number  and  add  to  the  general  comfort  and 
protection.     In  places  exposed  to  yellow-fever  infection  all   ! 
patients  should  be  protected,  nijiht  and  day,  from  the  bites  of  i 
quitoes  by  the  use  of  netting  and  wire  screens.     Strict  quarantine 
measures,  local  and  general,  with  the  isolation  of  patients  and  «-\ ten- 
sive and  thorough  fumigation  of  the  localities  where  they  are  found 
will  insure  suppression  of  the  disease  wherever  it  may  appear. 

In  the  suppression  or  control  of  yellow  fever  disinfection,  apart  f  i  <  »m 
fumigation,  is  a  waste  of  time  and  money.  Natural  yellow  fever  is 
transmitted  by  the  mosquito,  and  always  and  only  by  the  mosquito. 
The  harmlessness  of  fomites  has  been  fully  demonstrated  by  our 
experiments  in  1900  and  1901,  in  which  three  young  Americans  slept 
for  20  consecutive  nights  in  a  room  garnished  with  articles  soiled  with 
black  vomit,  bloody  fecal  discharges  and  urine  from  fatal  and  other 
cases  of  yellow  fever.  Three  and  four  large  boxes  were  packed  and 
unpacked  with  these  articles  night  and  morning  by  these  nommmu 
who  suffered  no  disturbance  of  health  from  these  exposures.  The 
room  was  20  feet  by  14  feet,  double  walled,  tightly  ceiled.  Iieated  to 
above  90°  F.  and  dark.  Water  was  always  present  to  keep  the  at  i 
phere  moist.  Two  other  nonimmunes  then  occupied  the  room  1« 
nights  while  additional  articles  of  bedding  and  clothing  were  added. 
They  slept  in  the  garments  and  between  the  sheets  that  had  covered 
cases  of  yellow  fever,  some  of  which  were  fatal.  The  result  of  this 
second  exposure  was  nil.  A  third  attempt  was  then  made  with 
additional  nonimmunes  equally  without  success.  Not  the  slight* >>t 
indisposition  followed  close  anil  intimate  contact  with  this  repulsive 
material  in  any  case.  Temperatures  and  pulse  rates  were  recorded 
at  regular  and  frequent  intervals.  Four  or  these  seven  noniinnmnes 
were  subsequently  infected  by  blood  injections  and  by  means  of 
infected  mosquitoes.  A  fifth  resisted  the  mosquito  once  (28)  and 
declined  further  attempts  at  inoculation. 

Yellow  fever  has  been  eradicated  from  Habana,  one  of  its  endemic 
homes,  by  the  institution  of  measures  directed  against  the  mosquito, 


YELLOW   FEVEE.  185 

after  extreme  cleanliness  and  energetic  disinfection  had  proved  a 
dismal  failure.  Several  cases  subsequently  imported  into  that  city 
have  been  handled  with  impunity  by  guarding  the  patients  against 
the  bites  of  those  insects.  A  small  outbreak  in  Santiago  de  las  Vegas 
in  1901  was  promptly  suppressed  by  Col.  Gorgas  by  the  use  of  mean 
directed  only  against  the  mosquito.  On  those  who  decline  to  accept 
such  evidence  must  rest  the  burden  of  proving  that  the  disease  is 
transmitted  in  some  other  way  before  their  position  can  be  sustained. 


REFERENCES. 


(1)  Medical  Inquiries  and  Observations,  Benjamin  Rush,  M.  D.,  Philadelphia,  1805 
vol.  iv.,  pp.  10,  77,  175. 

(2)  An  Essay  on  Yellow  Fever,  by  B.  B.  Strobel,  M.  D.,  Charleston,  S.  C.,  1840,  p. 
162. 

(3)  Report  of  Sanitary  Commission  of  New  Orleans  on  the  Epidemic  of  Yellow  Fever 
of  1853,  New  Orleans,  1854,  vol.  i,  pp.  266,  278,  540. 

(4)  The  Epidemics  of  New  Orleans,  by  Bennett  Dowler,  New  Orleans,  1854,  p.  44. 

(5)  La  Roche  on  Yellow  Fever,  Philadelphia,  1855,  vol.  i,  pp.  67,  77,  79. 

(6)  See  footnote  2,  p.  87,  citing  from  the  London  Medical  Gazette  for  August,  1839. 

(7)  New  Orleans  Med.  and  Surg.  Jour.,  May,  1900. 

(8)  Medical  Record,  N.  Y.,  June  15, 1901. 

(9)  Anales  de  la  Academia  de  Ciencias  Medicas  de  la  Habana,  Havana,  xxvii, 
1890-91.  p.  501.     (Finlay.) 

(10)  Original  Article — republished   in  English  in  the    Reyista  de  la  Asociacion 
Medico-Farmaceutica,  Havana,  Cuba,  Jan.  and  Feb.,  1902.     (Finlay.) 

(11)  Finlay:  Ibid.,  pp.  362  and  369;  also  Edinburgh  Med.  Jour.,  Oct.,  1894,  p.  334. 

(12)  Proceedings  of  the  International  Congress  of  Hygiene  and  Demography,  Buda- 
pest, 1894,  p.  702. 

(13)  Edinburgh  Med.  Jour.,  vol.  xli,  1  pp.  523  to  526. 

(14)  Finlay:  Amer.  Jour.  Med.  Sci.,  n.  s.,  vol.  xcii,  1886,  pp.  402,  403. 

(15)  Footnote  to  p.  369,  Revista  de  la  Asociacion  Medico-Farmaceutica,  Havana, 
Feb.,  1902. 

(16)  Medical  Record,  N.  Y.,  Feb.  9,  1901,  p.  203. 

17)  The  Journal  A.  M.  A.,  April  13, 1901,  p.  1041. 

18)  Ibid.,  Feb.  16,  1901,  p.  439;  3d  conclusion. 

19)  Medical  Record,  Aug.  31,  1901,  p.  344. 

(20)  Case  8  of  Dr.  Guiteras'  series,  Amer.  Med.,  Nov.  23, 1901. 

(21)  See  reprint,  p.  8,  on  "Method  of  Stamping  Out  Yellow  Fever,  Etc.,"  by  Dr. 
Charles  Finlay,  M.  D.,  Conference  of  State  and  Provincial  Boards  of  Health,  New 
Haven,  Conn.,  Oct.,  20, 1902,  and  Medicine,  Detroit,  March,  1903,  pp.  175, 179. 

(22)  Phila.  Med.  Jour.,  Oct.  27, 1900. 

(23)  Sternberg,  Amer.  Jour.  Med.  Sci.,  new  series,  vol.  cii,  1891,  p.  627,  and  Nuttall, 
Johns  Hopkins  Hosp.  Reports,  vol.  viiii,  1899-1900,  p.  27. 

(24)  Amer.  Med.,  Nov.  23, 1901. 

(25)  The  Journal  A.  M.  A.,  Feb.  16, 1901. 

(26)  Finlay:  Edinburgh  Med.  Jour.,  Oct.,  1894,  p.  335. 

(27)  The  Etiology  of  Yellow  Fever,  Amer.  Med.,  Feb.  22,  1902,  Case  2. 

(28)  Case  22,  Table  2. 


CHAPTER  2. 

ARKS  ON  EPIDEMIC  OF  YELLOW  FEVER  IN  BALTIMORE.' 
By  JAMBS  CARROLL,  M.  D.,  Burgeon  United  States  Army,  Washington,  D.  C. 

MR.  PRESIDENT  AND  GENTLEMI  \   <>r  THE  ALTJMM    taaa  EATI 
Instead  of  a  strictly  technical  theme.  I  liave  chosen  one  that  may 
f  more  general  interest,  and  which  formerly  demanded  the  at  ten- 
tin  n  of  two  of  the  most  brilliant  minds  among  the  early  teachers  of 
the  university. 

Dr.  Nathaniel  Potter,  a  former  pupil  of  Dr.  Benjamin  Ku-h,  and 
afterwards  the  first  professor  of  theory  and  practice  of  medicine  in 
the  university,  held    in   1703  that  yellow  fever  was  n«.t   emit a«:ious, 
and  he  communicated  this  opinion  to  Dr.  Rush  in  writing.    A 
to  his  own  statement,  he  believed  that  he  was  the  only  person  in 
America  who  held  that  opinion,  and  in  1795  he  prepared  to  defend 
his  belief  in  an  inaugural  thesis  to  be  read  at  the  next  comm- 
inent  of  the  University  of  Pennsylvania,  of  which  he  was  a  student. 
He  was  dissuaded  by  Dr.  Wistar  on  the  grounds  of  propriety 
expediency.     Dr.  Potter  states  that  in  1797  Rush  >  contention  that 
the  disease  was  contagious  was  first  publicly  attacked  by  I>r. 
B.  Davidge,  one  of  the  founders  ana  the  first  professor  of  sur 
and  obstetrics  in  this  school,   whose  paper  was  published    in 
Federal  Gazette,  of  Baltimore,  on  the  30tn  day  of  November.  17'.'7. 
Dr.  Davidge  subsequently  enlarged  his  paper  n  ..lied  it  in  a 

volume  entitled  "Physical  Sketches,"  published  in  Baltimore  in  1814. 
On  account  of  the  importance  of  this  city  as  a  seaport,  in  almost 
constant  intercourse  with  the  West  Indies,  yellow  fever  JUUM  have 
been  introduced  a  great  many  times,  yet  the  only  important  epi- 
demic outbreaks  of  the  disease  took  place  in  17iM.  17(>7,  1800,  and 
1819.  It  is  notable  that  all  the  outbreaks  began  at  Locust  Point, 
or  about  the  docks  and  wharves,  and  they  can  DC  traced  direct  I 
indirectly  to  the  shipping.  The  relatively  high  ground  upon  which 
the  city  stood,  and  tne  distance  from  the  city  proper  to  the  wh.-; 
and  shipping,  explain  why  the  intcrurban  residents  suffered  but  little, 
while  those  Jiving  upon  the  poorly  drained,  low-lying  di  near 

the  river  were  compelled  on  such  occasions  to  flee  for  saf < 

It  can  be  easily  shown  that  yellow  fever  was  frequently  confounded 
with  malaria;  indeed,  it  was  strongly  contended  that  the  t\\«>  di- 
eases  were  one  and  the  same,  tl  nee  being  only  in  the  .1. 

of  intensity.     Then,  while  many  contended   that    the  disease 
imported,  and  though  their  contentions  could  be  supported  by  sworn 
testimony,  there  were  others  among  the  leaders  and  teachers  in  the 
profession  who  held,  \\ith   Ku>h,  that  since  the  infection  was  j: 
prevalent  in  poorly  drained  localities,  the  water  and  decomp 
vegetable  matter  must  be  necessary  for  the  generation  of  the  poison, 
which    was    manifestly    conveyed    through    the    atmosphere.     The 

•  Hoipital  li  venlty  of  Maryland,  Feb.  15, 1905. 


YELLOW   FEVER.  187 

general  restriction  of  the  disease  to  the  localities  described,  the 
observation  that  many  persons  who  visited  those  localities  for  only  a 
few  hours  became  infected,  while  in  other  localities  no  infection  took 
place,  even  among  those  who  were  intimately  associated  with  the 
patients,  proved  the  disease  to  be  one  of  locality.  With  the  observa- 
tion that  if  the  wind  blew  strongly  from  the  direction  of  the  infected 
locality  toward  the  city,  that  within  a  few  days  the  disease  also  ex- 
tended toward  the  city,  it  was  concluded,  with  reason,  that  the  poison 
must  exist  in  the  atmosphere,  that  it  was  transported  by  the  winds, 
and  that  infection  could  only  result  from  the  inhalation  of  this  poison, 
which  was  believed  to  be  gaseous  in  nature.  This  agreed  with  Syd- 
enham's  theory  of  the  epidemic  constitution  of  the  atmosphere,  which 
was  supported  by  Rush  and  his  pupils,  and  which  then  seemed  to 
offer  the  only  explanation  of  the  recorded  observations  of  centuries. 
If  we  admit  the  mosquito  as  the  sole  carrier  of  the  disease,  we  will 
be  prepared  to  acknowledge  that  their  observations  were,  in  the 
main  points,  strictly  accurate;  that  their  reasoning  was  logical,  and 
the  deductions  fully  justified  by  the  premises.  It  then  becomes  very 
easy  to  understand  how  the  disease  became  one  of  lowly  situated 
and  poorly  drained  localities;  how  it  was  transmitted  by  the  atmos- 
phere ;  how  it  failed  to  spread  in  certain  locations ;  and  how  it  dis- 
appeared upon  the  appearance  of  a  heavy  frost.  The  observation 
was  actually  recorded  by  a  Baltimore  physician  that  during  the 
epidemic  mosquitoes  became  an  intolerable  pest,  while  but  a  short 
time  before  no  mosquitoes  were  observed. 

How  beautifully  this  observation  agrees  with  our  present  knowl- 
edge that  the  yellow-fever-carrying  mosquitoes  can  be  conveyed  on 
vessels ;  that  in  the  warmer  season  of  the  year  they  will  multiply  on 
shore,  gradually  extending  from  house  to  house,  breeding  in  and 
about  the  dwellings  (for  they  are  domesticated  insects),  and  that 
they  become  infected  only  after  feeding  upon  a  patient.  The  impor- 
tation of  the  mosquito  explains  the  appearance  of  this  insect  in  places 
where  it  usually  does  not  exist;  it  explains  the  occurrence  of  the 
earlier  cases  among  persons  who  either  visited  the  vessels  or  wharves 
or  docks,  or  who  lived  in  the  vicinity  of  them.  It  also  explains  why 
favorable  localities  were  visited  by  the  infection  only,  as  a  rule,  when 
they  received  shipping;  while  localities  equally  favorable  to  the 
infection,  but  far  from  the  shipping,  remained  free  from  it.  Of  course, 
the  absence  of  the  proper  mosquito  explains  the  failure  of  the  disease 
to  spread  to  any  extent  in  the  city  proper.  This  stood  upon  ground 
that  was  high  and  dry,  and  it  was  at  that  time  some  distance  from 
Fell's  Point,  the  location  of  Sugar  House  Wharf  where  many  of  the 
vessels  from  the  West  Indies  probably  made  their  landing.  Assum- 
ing that  at  the  Sugar  House  Wharf  cargoes  of  sugar  were  unloaded, 
we  are  reminded  that  sugar  is  a  favorite  food  for  the  yellow-fever 
mosquito,  and  that  it  can  subsist  on  this  and  water  alone  for  months. 
Now  Sugar  House  Wharf  was  at  Fell's  Point,  and  most  of  the  out- 
breaks began  at  Fell's  Point,  where,  presumably,  the  largest  number 
of  mosquitoes  was  imported. 

During  the  epidemic  of  1794,  360  deaths  were  recorded.  Dr. 
Drysdale  reported  *  that  he  saw  his  first  case  just  before  death  on  the 
7th  of  August,  at  Bowley's  Wharf,  in  the  town,  and  on  the  14th, 

» The  Philadelphia  Medical  Museum,  1805, 1 26.    Letters  written  by  Dr.  Drysdale  to  Dr.  Rush. 


188  YELLOW  FEVER. 

20th,  22d,  and  23d  of  the  same  month  he  saw  five  additional  < 
at  the  same  part  of  the  wharf.  There  \\ere  also  at  the  same  place 
some  other  cases  which  did  not  come  under  his  care.  Dr.  Prysdale 
states  that  there  was  considerable  sickness  at  Fell's  Point  after  the 
death  of  his  first  case,  and  many  deaths  had  occurred  suddenly, 
«>r  after  a  short  indisposition.  An  investigation  was  made  l>y  three 
of  the  most  respectable  physician-,  who  reported  that  the  prevailing 
•r  was  the  common  epidemic  of  the  season  which  visited  the 
Southern  and  Middle  States  annually,  viz,  the  bilious  remit  tent 
fever.  The  number  of  cases  now  rapid  Iv  increased,  so  that  1>\ 
tember  25,  in  about  seven  weeks,  five  physicians  were  attacked  and 
two  of  them  died.  The  cases  had  become  so  numerous  that  Dr. 
Coulter  visited  and  prescribed  for  more  than  120  per-"ii-  daily.  By 
the  end  of  the  month  many  families  had  sought  refuse  in  the  country. 
During  this  time  the  city  remained  unusually  healthy,  and  although 
some  persons  infected  at  the  Point  died  in  the  city  proper,  in  that 
location  the  disease  failed  to  spread. 

In  his  ninth  letter  of  a  series  to  Dr.  Rush  he  state-  that  yellow 
fever  was  first  discovered  at  two  points,  remote  from  each  other,  vi/. 
at  Bowleys  Wharf  in  the  town-,  and  at  Fells  Point.  Many  cases 
occurred  throughout  the  town,  but  these  originated  either  from  com- 
munication with  Bowleys  Wharf  or  the  roint,  and  the  infection 
could  be  distinctly  traced  to  one  of  those  two  places.  Beinir  pn//led 
to  explain  why  the  infection  was  confined  to  those  two  places,  he 
found  that  the  first  cases  on  the  Point  were  confined  to  h< 
whose  cellars  were  filled  with  stagnant,  putrid  water,  and  he 
found  black,  putrid,  and  offensive  water  beneath  the  stores  in  which 
the  sick  resided  at  Bowleys  Wharf.  Almost  all  those  who 
first  affected  were  newcomers.  Dr.  Drysdale  describes  the  Point 
as  being  low  and  flat;  its  streets  generally  not  paved;  its  alleys 
filthy,  and  the  ground  around  it  marshy  in  many  places.  The 
frequent  warm  rains  kept  the  noxious  places  constantly  moi>t  under 
a  hot  sun.  We  can  easily  recognize  these  as  conditions  favoraLle 
to  the  multiplication  of  mosquitoes,  and  the  domestic  habits  of  the 
stegomyia  mosauito  would  tend  to  keep  the  infection  rather  do-ely 
confined  to  these  localities.  He  further  makes  the  significant 
statement  that  remittents  were  present  from  a  very  early  period. 
It  is  more  than  probable  that  many  of  these  remittents  were  true 
yellow  fever,  because  under  the  belief  then  prevailing,  that  these 
were  simplv  the  prevailing  types  of  summer  fever,  they  would  not 
be  reported..  It  is  also  probable  that  if  occasional  cases  were  known 
to  have  been  yellow  fever,  some  physicians  would  have  concealed 
them  from  the  same  motives  that  prevail  to-day.  He  could  discover 
no  satisfactory  evidence  of  the  importation  of  the  disease,  though  he 
states  that  the  Triumph  arrived  at  the  wharf  about  the  last  of  June, 
with  almost  all  the  crew  indisposed,  and  previous  to  this  there  lay 
at  the  wharf  a  schooner  whose  captain  had  died  on  the  voyage  from 
the  West  Indies.  The  fact  alone,  however,  that  vessels  from  the 
West  Indies  came  up  to  the  wharf  is  sufficient  to  indicate  to  us 
the  source  from  which  the  infection  was  received.  The  following 
sentence  toward  the  end  of  the  ninth  letter  is  of  extreme  interest: 
"Locusts  were  not  more  numerous  in  the  reign  of  Pharaoh  than 
mosquitoes  through  the  last  few  months;  yet  these  insects  were  very 
rare  only  a  few  years  past,  when  a  far  greater  portion  of  Baltimore 


YELLOW   FEVEK.  189 

was  a  marsh."  With  wonderful  acuteness  of  observation  he  remarks 
that  some  families  at  the  Point  avoided  yellow  fever  by  carefully 
precluding  all  communication  with  the  sick,  and  that  vessels  also 
preserved  their  crews  in  health  by  removing  to  a  distance  from  the 
wharf  and  preventing  the  sailors  from  going  ashore.  As  soon  as  one 
infected  person  came  on  board  he  quickly  infected  all  or  most  of  the 
crew.  He  instances  one  man  who  contracted  the  disease  on  shore 
and  carried  it  on  board  the  ship  PTioenix,  whose  crew  was  healthy. 
These  all  became  infected  and  5  out  of  12  died.  As  the  result  of 
these  observations  he  very  naturally  concluded  that  in  some  instances 
the  fever  proved  contagious.  These,  and  other  cases  cited,  are 
now  so  easily  explained  by  the  mosquito  theory  that  we  can  not 
appreciate  the  perplexity  of  the  problem  as  it  formerly  presented 
itself  for  solution.  The  most  accurate  and  careful  observation 
yielded  results  that  were  apparently  contradictory.  All  honor  to 
Dr.  Drysdale,  whose  tenth  and  last  letter  of  the  series  was  written 
to  Dr.  Rush  in  December,  1794. 

Some  further  interesting  references  to  this  epidemic  were  published 
by  Dr.  John  B.  Davidge  in  1798  and  subsequently  rewritten  by  him 
in  a  treatise  on  yellow  fever,  published  in  1813.  He  makes  the  inter- 
esting statement  that  the  yellow  fever  first  appeared  in  the  last  of 
August,  but  the  common  bilious  fever  prevailed  at  Fells  Point  from 
June.  A  lady  from  Philadelphia  was  attacked  with  yellow  fever, 
on  Charles  Street,  and  she  had  black  vomit,  but  no  other  person  in 
the  family  or  neighborhood  was  attacked  during  the  whole  season. 
He  no  ted 'that  the  disease  extended  in  the  direction  of  the  prevailing 
winds,  and  that  it  was  conveyed  bv  a  northeast  wind  all  along 
Federal  Hill  and  the  west  end  of  the  basin.  A  considerable  number 
of  cases  occurred  in  the  city  and  many  who  had  attended  the  launch- 
ing of  a  frigate  (near  the  water,  of  course),  subsequently  suffered 
from  yellow  fever,  and  several  of  them  died,  but  no  single  person  in 
the  city  contracted  the  disease  from  them. 

Concerning  the  prevalence  of  yellow  fever  in  Baltimore  at  that 
time  (1798),  Dr.  Davidge  writes: 

A  physician  in  conversation  the  other  day  told  me  that  he  had  met  with  the  yellow 
fever  in  Baltimore  ever  since  he  had  lived  there,  which  is  15  or  20  years.  It  is  vio- 
lating all  obligations  of  decency  and  truth  to  say  that  it  is  of  recent  date. 

This  statement  was  probably  correct,  for  every  importation  of  the 
disease  is  not  necessarily  followed  by  an  epidemic.  In  Baltimore 
and  other  places  where  the  mosquito,  Stegomyia  fasciata,  is  not 
normally  present,  an  epidemic  is  not  possible,  after  the  introduction 
of  any  number  of  cases,  provided  the  mosquito  be  absent.  For  the 
production  of  an  epidemic  the  introduction  of  infected  mosquitoes 
alone  during  the  hot  season  may  suffice,  because  the  mosquitoes 
deposit  their  eggs,  and  in  a  week  or  10  days  another  brood  will  have 
become  mature.  The  insects  of  this  new  brood  must  bite  a  patient 
in  the  first  three  or  four  days  of  the  attack  in  order  that  they  may 
become  infected.  Should  only  one  or  two  infected  insects  be  brought 
in  and  should  they  die  (as  frequently  happens)  immediately  after 
depositing  their  eggs,  then  the  disease  would  appear  only  in  the 
persons  first  bitten  by  them,  and  these  would  have  passed  beyond 
the  infective  period  by  the  time  the  new  brood  had  matured.  Should 
the  infected  insects,  however,  have  remained  alive,  and  should  they 
have  bitten  other  persons,  at  intervals  of  a  few  days  in  succession, 


190  YELLOW  PEVBB. 

these  persons  would  be  in  the  proper  stage  of  the  disease  at  the 
maturini:  of  the  new  brood  to  enable  them  to  become  infected. 
When  the  proper  mosquito  has  been  previously  introduced  into  a 
favorable  locality  in  the  proper  season,  or  when  the  mosquito, 
Sttgomyia  fascia  /J/.i-  naturally  present,  the  introduction  subsequently 
of  a  single  case  may  produce  an  epidemic.  The  facts  above  stated 
will  readily  explain  the  frequently  reported  appearance  of  sporadic 
cases  without  the  occurrence  of  secpncfary  ones. 

We  can  now  see  that  the  immunity  against  the  disease  enjoyed  by 
proper  evidently  depended  upon  its  high   and  dry  location. 
ndered  the  conditions  unfavorable  for  the  multiplicai  inn  of 
the  mosquitos  that   were  imported.     In  tin-  regard    Baltimore 
more  fortunate  than   Philadelphia,  which  was  lower  and  contained 
B  standing  water.     Hence,  the  mosquitos  were  more  abundant 
and  the  disease  spread  uniformly.     This  led  Dr.  Rush  to  contend  that 
the  disease  must  be  contagious,  while  Dr.  Davidire  held  t  hat  t  he 
tairion  was  local,  and  existed  only  in  the  air  of  certain  fmm 

where  it  might  be  wafted  by  the  winds  in  any  direction.     Dr. 
asserted  (p.  84)  that  they  had  the  m<»t  stubborn  and  in. 
proofs,  in  those  cases  occurr  in  L:  about  the  whar\ex  ;(nd  at   I-VIU  Point. 
that  the  disease  was  incapable  of  supporting  it  >elf.     When  these- 
noved  u]>  into  the  city  their  virulence  died  with  them,  i 
who  died;  and,  he  writes,  "from  those  who  recovered,  all  mischief  and 
supposed  contagion  evanesced  into  empty  air.  which  bore  it  to  the 
pages  of  medical  writers,  and  not  to  the  bodies  of  healthy  attendants. 
This  was  the  result  in  1794  and  1797." 

The  importance  of  tin's  observation  can  hardly  be  overestim.: 
it  shows  the  sagacity  and  care  with  which  the  epidemic  was  studied 
by  these  devoted  men.     Dr.  Davidge  learned  the  truth,  and  that 
truth  unfortunately  still  remains  to-day  a  hidden  mystery  to  many 
of  our  practitioners,  notwithstanding  the  recent  absolute  demon 
tion  of  it  beyond  a  shadow  of  a  doubt. 

In  connection  with  the  now  known  mosquito  propagation  of  the 
disease,  an  observation  recorded  by  Dr.  Nathaniel  Potter  '  in  this 
outbreak  of  1797  deserves  mention.  He  tells  us  that  previous  to  the 
17th  of  September  the  fever  had  been  conlined  to  certain  place-  and 
to  such  as  had  breathed  the  air  evolved  from  them:  on  that  <! 
strong  southeast  wind  wafted  the  effluvia  in  a  northwest  direction 
and  diffused  it  among  the  inhabitants  of  the  upper  part-  of  I  ied- 
erick,  Gay,  South,  and  Calvert  Streets,  who  became  immediately 
implicated  in  all  the  horrors  of  the  fever. 

In  1800  there  appeared  the  severest  outbreak  the  city  has  Known. 
The  mortality  from  yellow  fever  is  recorded  to  have  been   1  .  l'.»7.  or 


about  1  in  50  of  the  population  of  60,000.     Again  the  di>ea-e  I 
at  Fells  Point,  on  the  borders  of  the  cove,  which  extended   from 
Jones  Falls  to  the  interior.     The  faculty  of  medicine  of  the  city,  after 
investigation,  reported  to  the  mayor  that  in  their  belief  the  disease 
was  i  or  ted.  but  originated  in  t  he  cove  from  thostagnat  ion 

putrefaction  of  filth  un«i.  'iimer's  sun.     The  fir-:   t  v.  o 

peared  on  the  2d  of  May,2  another  on  the  Sth  of  June,  one  on  the 
9th,  10th,  and  Kith:  then  from  the  -I'd  they  became  more  mime. 


-  .««~..  on  Contagion,  by  Nathaniel  Potter,  M   D.,  Baltimore,  1818,  p.  20. 

*  Medical  Repository,  New  York,  1801,  vol.  IV.  p.  361. 


YELLOW   FEVEE.  191 

It  is  unfortunate  that  we  have  no  detailed  description  of  this  epi- 
demic, the  most  disastrous  the  city  has  ever  experienced. 

A  few  cases  are  reported  for  the  years  1802-1805. 

The  next  important  outbreak  took  place  in  1819  following  the 
arrival  of  an  infected  ship  from  Habana.1  In  a  letter  to  the  editors 
of  the  Medical  Repository,  Dr.  Pierre  Chatard,2  of  Baltimore,  writing 
October  19,  cites  the  first  cases  as  follows:  The  fever  commenced 
raging  at  Fells  Point  in  the  beginning  of  July,  and  never  ceased  there 
until  the  end  of  October.  It  appeared  also  at  Smith's  Dock  toward 
the  end  of  July,  carrying  off  five  persons  whose  names  are  given,  and 
others.  The  persons  named  had  countinghouses  on  the  dock  or  in 
the  vicinity.  m>  other  cases  appeared  at  the  dock  for  two  months, 
at  the  end  of  which  time  two  more  appeared.  Dr.  Chatard  attributes 
the  absence  of  cases  during  this  time  to  the  great  quantity  of  lime 
that  had  been  strewn  on  the  ground  by  order  of  the  mayor.  The  lime 
was  again  applied  and  the  cases  ceased.  At  Fells  Point  the  disease 
raged  for  three  months  before  it  subsided.  The  greater  part  of  the 
population  retired  to  the  healthier  portions  of  the  city,  and  many  of 
them  sickened  and  died  there,  but  none  of  their  friends  or  relatives 
suffered  in  consequence.  We  are  told  by  Dr.  Chatard  that  the 
epidemic  focus  on  the  Point  never  exceeded  seven  or  eight  thousand 
square  feet.  This  information  he  regarded  as  precious  because  it 
demonstrated  the  noncontagiousness  of  the  disease  and  the  value  of  a 
local  quarantine. 

Among  the  most  interesting  records  of  this  epidemic  are  the  letters 
and  other  documents  published  by  authority  of  the  mayor  in  1820. 
These  contain  the  actual  opinion  and  experiences  of  the  physicians, 
and  they  show  a  remarkable  unanimity  in  the  belief  among  the  Balti- 
more physicians  that  the  disease  was  noncontagious.  The  persist- 
ency with  which  the  infection  originated  and  remained  in  the  vicinity 
of  shipping,  wharves,  etc.,  is  generally  commented  on.  Dr.  Clendinen 
reports  that  his  first  cases  were  located  at  the  southeast  corner  of 
Fells  Point,  and  several  of  them  appeared  among  foreigners  on  board 
the  shipping,  persons  who  had  been  healthy  previous  to  their  arrival. 
This  invasion  by  the  disease  of  healthy  ships  tied  up  to  the  wharves 
appeared  to  be  indisputable  evidence  of  the  poisoned  condition  of  the 
atmosphere.  Of  course  it  is  hardly  necessary  to  say  here  that  these 
vessels  were  simply  invaded  by  infected  mosquitoes.  Dr.  Clendinen 
was  a  resident  of  the  Point,  and  he  states  that  his  family  had  suffered 
from  the  disease  and  he  had  lost  a  student,  an  assistant  physician, 
and  some  of  his  best  friends.  Dr.  Samuel  B.  Martin,  after  enumerat- 
ing 34  of  his  earlier  cases,  with  their  location  about  the  wharves  and 
shipyards,  states: 

These  will  suffice,  I  think,  to  show  the  course  the  disease  took  in  its  commencement, 
traveling  regularly  along  the  course  of  the  water  and  infecting  the  streets  in  the  vicinity 
thereof.  My  most  violent  cases  were  near  the  water's  edge  or  contracted  there. 

No  mention  of  this  epidemic  would  be  complete  without  a  reference 
to  the  little  book  by  Dr.  David  M.  Reese,  entitled  "  Observations  on 
the  Epidemic  of  181 9,"  a  book  which  every  one  interested  in  the 
subject  should  read.  According  to  him,  some  persons  attributed  the 
epidemic  to  the  arrival  of  the  schooner  Adventure  from  the  West 

1  Carpenter  on  Yellow  Fever,  New  Orleans,  1844,  p.  18. 

2  Medical  Repository,  New  York,  vol.  20, 1820,  p.  261. 


192  W>W    1KVER. 

Indies,  laden  with  coflfee,  while  others  looked  with  suspicious  eyes 
upon  the  schooner  Proserpine  laden  with  hides  and  coil'ee.  Both 
teasels  were  ordered  to  the  quarantine  -round,  hut  were  soon  per- 
mit ted  to  return  because,  after  a  reexamin  at  ion  hy  the  health  ollicer, 
their  cargoes  were  found  to  be  in  a  sound  condition. 

ingto  the  time  when  1,016  cases  had  been  reported  hy  the 
physicians,  Dr.  Reese  states  that  of  all  of  these  only  rj  were  supposed  t<> 
nave  originated  in  the  city.  He  calls  attention  to  the  remarkahle 
fact  that,  in  almost  every  instance  where  a  person  visited  the  Point 
at  niirht  the  contracted  they  disease,  while  those  who  were  there  only 
in  the  daytime  escaped  with  impunity.  He  further  remarks  that 
those  of  tne  Baltimore  physicians  who  became  infected  sullVred  in 
consequence  of  paying  a  \  i-it  hy  ni.Lrht  to  the  source  of  infection,  or 
to  the  vicinity  where  the  cause  existed.  Several  ph  \\  h<  >  had 

attended  patients  in  the  daytime  in  the  very  cent er «•!'  the  infection. 
and  through  the  whole  course  of  the  fever  remained  exenmt  until  hy 
vi-itini:  the  district  once  in  the  night  they  contracted  tne  di 
This  accords  perfectly  with  the  mosquito  theory  and  wit  h  t  he  t  wili«rlit 
habits  of  stegomyiafasciata,  the  particular  mosquito  n«  >w  know  n  ' 
concerned  in  the  transmission  of  the  disease.  It  i>  al-o  in  accord  with 
the  experience  of  the  American  troops  near  Habana.  Soldiers  who 
visited  the  city  only  between  the  hours  of  9  a.  m.  and  4  p.  in.  remained 
free  from  the  disease,  while  among  those  who  became  infected  there 
were  but  few  who  did  not  acknowleo!ge  having  spent  a  niirht  or  a  part  of 
anight  out  of  the  barrack.  Let  us  now  consider  what  evidence,  if  any, 
collected  by  these  closely  observant  Baltimore  physicians  could  he 
used  to  support  the  mosquito  theory  to-day.  Firstly,  t  i  nied 

the  presence  of  an  unusually  large  number  of  mosquitoes;  secondly, 
they  observed  that  the  infection  was  localized  in  the  low,  wet  disi  rid  s 
near  the  river  and  shipping;  thirdly,  they  noted  that  the  infection  was 
contracted  mostly  at  night;  fourthly,  they  showed  that  in  the  higher 
and  drier  ground  of  the  city  proper  the  disease  was  absolutely  non- 
contagious;  fifthly,  they  reported  that  the  disease  traveled  in  the 
direction  of  the  prevailing  winds,  wrhen  these  were  strong  and  hlew  in 
one  direction ;  and,  sixthly,  they  were  familiar  with  the lact  that  yel- 
low fever  was  most  apt  to  prevail  when  the  mean  temperature  was 
high,  and  they  knew  perfectly  well  that  the  disease  was  stamped  <.m 
by  the  frost.  To  this  we.  can  add  nothing  more  than  the  direct. 
implication  of  the  mosquito. 

Of  course,  a  mistake  was  made  in  the  failure  to  recognize  the 
imported  nature  of  the  disease,  and  strong  protests  were  written 
against  the  quarantine  methods  then  in  force  against  Baltimore  by 
Philadelphia,  Wilmington,  and  other  places.  These  *  quarantines 
were  established  in  the  belief  that  the  disease  was  contagious,  The 
Baltimore  physicians,  having  the  strongest  proofs  that  it  was 
felt  that  they  were  treated  with  undue  seventy.  In  a  low-lying  city 
like  Philadelphia,  where  mosquitoes  were  numerous,  there  was  JIM  i- 
fication  for  the  belief  in  contagion,  so  that,  while  both  were  partly 
wrong  in  their  opinions,  under  the  circumstances  the  method  of 
Quarantine  was  a  justifiable  and  proper  one  to  adopt  for  their  sal 
On  the  other  hand,  the  lax  cjuanmtine  system  at  Baltimore  was  a 
source  of  danger;  still  it  was  justifiable  on  the  ground  of  the  availa- 
ble evidence  to  show  that  yellow  fever  was  not  contagious  and  upon 
the  belief  then  prevailing  that  all  infectious  fevers  were  the  result 


YELLOW   FEVER.  193 

of  putrefaction.  Hence,  if  a  vessel  were  clean  and  her  cargo  in  good 
condition,  it  was  assumed  that  she  could  not  harbor  the  seeds  of  the 
disease  and  she  was  permitted  to  come  into  dock  and  unload. 

In  the  management  of  the  epidemic  the  wise  policy  was  adopted  of 
advising  all  persons  to  flee  the  infected  location  and  seek  a  residence 
upon  high  ground  without  the  range  of  the  infection.  This  the  major- 
ity did,  many  going  to  the  country  or  remaining  nearby,  while  some 
refused  to  leave  their  habitations,  and  these  latter  furnished  the  fuel 
for  the  continuance  of  the  pestilence.  This  epidemic  is  said  to  have 
cost  the  city  350  lives. 

The  kindly  concern  shown  for  the  welfare  of  the  destitute  poor 
stands  out  brightly  in  the  history  of  this  outbreak.  It  became  nec- 
essary to  remove  the  healthy  poor  from  Fell's  Point  and  provide 
means  of  shelter  and  sustenance  for  them  until  it  was  safe  for  them 
to  return.  A  committee  was  appointed  who  visited  a  Mr.  Owen  Dor- 
sey  to  solicit  the  use  of  a  ropewalk  owned  by  him.  This  was  granted 
free  of  charge  and  the  removal  began.  More  room  was  soon  needed, 
and  a  Mr.  Christopher  Chapman  gave  up  another  adjacent  ropewalk, 
1,000  feet  long,  for  the  purpose.  This  was  not  sufficient  and  more 
than  100  tents  and  marquees  were  then  pitched  and  filled.  Over 
1,000  persons  were  received,  made  comfortable,  and  supplied  with 
provisions  and  every  necessity.  The  corporation  appropriated 
$1,000,  but  this  was  returned,  the  donations  of  money  and  supplies 
being  ample  for  all  purposes.  Notwithstanding  the  partial  depopu- 
lation, business  depression,  failure  of  some  of  the  leading  commer- 
cial houses  and  one  of  the  banks,  over  $4,000  in  cash  were  contrib- 
uted and  liberal  donations  of  food,  clothing,  etc.,  poured  into  the 
warehouses  designated  to  receive  them.  The  neighboring  farmers 
contributed  flour,  fruit,  and  vegetables  as  well  as  money,  and  George- 
town, D.  C.,  contributed  $700.  A  soup  house  was  established  at 
the  encampment,  and  this  supplied  over  100  gallons  of  rich,  whole- 
some soup  daily.  This  enterprise  was  undertaken  by  three  energetic 
gentlemen — Messrs.  Stewart,  Mosher,  and  Coale — and  through  vol- 
untary contributions  of  material  and  labor  the  total  outlay  required 
was  only  $10.  The  camp  was  maintained  for  53  days,  and  when  it 
was  broken  up,  on  the  25th  day  of  October,  each  person  was  sup- 
plied with  provisions  for  three  davs.  There  were  only  six  deaths 
in  the  encampment  and  five  additional  in  the  hospital  of  persons 
who  contracted  the  fever  at  the  Point  and  were  carried  from  the 
camp  to  the  hospital  for  treatment.  The  sick  among  the  poor  were 
cared  for  at  the  hospital  at  the  expense  of  the  city.  Food,  luxuries, 
and  stimulants  were  provided  for  distribution  upon  the  order  of  any 
practicing  physician.  It  is  estimated  that  by  these  means  several 
hundred  lives  were  saved,  and  the  record  is  one  of  which  Baltimore 
should  be  proud.  The  mayor,  Edward  Johnson,  was  a  man  of 
Christian  character,  high  courage,  and  strong  determination.  ^  Dis- 
regarding protests,  the  mayor  and  many  of  the  board  of  health  visited 
the  hospitals  during  the  height  of  the  epidemic,  and  by  their  example 
inspired  others  with  confidence  in  the  noncontagious  nature  of  the 
disease.  Dr.  Reese  wrote  of  him : 

Mr.  Johnson  is  one  of  the  few  individuals  with  whom,  when  interest  and  duty  are 
in  opposite  scales,  the  latter  will  ever  predominate. 

After  this  disastrous  epidemic  a  few  cases  occurred  annually  until 
1805,  and  perhaps  later. 

79965°— S.  Doc.  822,  61-3 13 


194  YELLOW   FEVER. 

Ton  cases  are  reported  to  have  appeared  at  Kort  McHenry  in  1^ 
and  the  disease  was  believed  to  conic  from  infect  Is  in  <|iiaran- 

tine  nearby.     It  is  probable,  as  has  been  stated  1>\  l>r.  John  M« 
sporadic  outbreaks  were    frequent    at     Kells   Point    until    1 
In    tliis   \car   I>r.    Kemp,   of   the   hoard   of   health,    had    (lie   infected 
district  drained  and  cleaned.     It  is  said  to  have  l>een  free  from  the 
ase  from  then  until  \cept  durin.i:  the  sii^pen>ion  of  com 

e  dnrinjr  the  Civil    \\'ar  .   \\hen   a   small   outhivak   <»f   the   t 
undoubtedly  appeared,  though  the  cases  \\ere  not  oilicially  reported. 

In   this  review  of  the  epidemics  at  Baltimore,   the  literatim 
which  is  very  scant,  I  have  confined  myself  to  a  simnle  narrati- 
the  facts  which  seem  to  be  of  general  interest,  and  I  nope  that  >ome 
«>u  mav  be  stimulated  to  read  for  yourselves  the  records  \\  ritten 
:ien  of  this  city,  some  of  whom  were  teacher-  in  our  university 
and  of  whom  you  have  every  reason  to  be  proud. 


i  History  of  the  Epidemic  in  Baltimore  in  1870.     Reports  of  American  Public  Health  Association.  Vol. 

>f,  p.  244. 

*  Baltimore  Physician  and  Surgeon,  Vol.  VI.  p.  37. 


CHAPTER  3. 

YELLOW  FEVER:  A  POPULAR  LECTURE.1 

By  JAMES  CARROLL,  M.  D.,  assistant  surgeon,  United  States  Army. 

Yellow  fever,  or  yellow  jack,  as  it  is  more  familiarly  called,  is  so 
far  as  our  knowledge  goes,  strictly  an  American  plague  or  pestilence, 
and  our  earliest  authentic  accounts  of  this  disease  record  its  occur- 
rence in  the  West  Indies  at  the  middle  of  the  seventeenth  century. 
By  one  or  two  of  the  older  writers  it  is  reported  to  have  been  trans- 
ported there  from  Siam,  but  this  seems  unlikely,  because  yellow 
fever  has  never  been  shown  to  be  an  oriental  disease.  Before  the 
time  of  Sydenham,  oriental  plague,  typhus  fever,  smallpox,  cholera, 
pernicious  malaria,  and  yellow  fever  were  all  called  putrid  or  pestilen- 
tial fevers;  it  was  believed  they  were  due  to  the  same  cause  and 
that  they  were  transmitted  through  the  atmosphere  as  visitations 
from  God.  At  that  time  the  science  of  medicine  stood  upon  such  a 
low  plane  that  the  best  English  physicians  were  just  beginning  to 
learn  that  there  were  differences  between  measles  and  smallpox, 
typhoid  fever  or  typhus  fever,  and  malaria,  etc.  Harvey  had  only 
recently  announced  the  circulation  of  the  blood  and  Malpighi  had 
followed  him  with  a  demonstration  of  the  blood  corpuscles  in  the 
smaller  vessels  (capillaries)  uniting  the  arteries  and  veins.  Peruvian 
bark,  that  blessing  in  malarial  fevers,  was  barely  known  at  the  time 
when  yellow  fever  first  prevailed  at  Barbados,  Jamaica,  Santo 
Domingo,  and  Martinique,  and  later  at  Vera  Cruz.  In  1761  the 
disease  was  carried  from  Vera  Cruz  to  Habana  by  the  Spaniards,  who 
lost  3,000  persons  from  it  in  that  year  alone,  and  in  1780,  out  of  an 
army  of  8,000,  about  2,000  died  of  yellow  fever  within  two  months 
after  landing  at  Habana.  It  is  further  reported  that  in  1794  there 
were  over  1,600  victims  to  yellow  fever  in  the  Spanish  garrison  and 
squadron  at  Habana.  More  recently,  for  the  10  years  from  1870  to 
1879,  inclusive,  11,746  deaths  are  recorded  for  the  city  of  Habana 
from  yellow  fever  alone.  Spain  paid  dearly  for  the  Pearl  of  the 
Antilles  in  both  men  and  treasure,  for,  besides  decimating  her  troops 
in  Cuba,  the  disease  followed  them  across  the  Atlantic  and  appeared 
in  epidemic  form  in  various  cities  of  the  Peninsula  from  time  to  time. 

The  fearful  mortality  attendant  upon  this  disease  is  well  brought 
out  in  the  accounts  of  some  of  these  epidemics.  For  instance  we  are 
told  by  an  English  physician,  Dr.  O'Halloran,2  who  studied  the  epi- 
demic in  Barcelona  hi  1821,  that  the  general  hospital  received  830 
patients  suffering  from  yellow  fever,  and  of  these  no  less  than  749,  or 
90  per  cent,  died.  This  keen  observer  contends  the  disease  can  not  be 
contagious,  but  is  due  to  some  local  infection  of  the  atmosphere,  and 
in  support  of  his  contention  he  cites  numerous  instances  during  the  out- 

1  Delivered  at  Galveston,  Tex.,  Apr.  12, 1905,  under  the  auspices  of  the  University  of  Texas.    Reprinted 
from  American  Medicine,  Vol.  IX,  No.  22,  pp.  907-915,  June  3, 1905. 

2  Remarks  on  the  Yellow  Fever,  by  Thomas  O'Halloran,  M.  D.,  London,  1823. 


196  YELLOW   FEVER. 

break  referred  to,  showing  the  disease  was  not  aiul  could  not  be  di- 
rectly contagious,  because  duriiu:  the  epidemic  thousands  of  persons 
fled  from  the  city  to  the- country.  iiMshiaing  those  who  had  slept  with, 
nursed,  and  been  intimately  associated  with  the  sick.  traveling  in  many 
instances  in  the  same  cart-  <>r  carriages  that  had  been  the 

transportation  of  nalicnis.  and  e\cn  the  dead,  and  after  carry  in;;  with 
them  the  penoiuJ  cll'ects  of  those  who  had  died  of  the  disease.     Still. 
;her  cases  f.>ll..\\ed  in  the  districts  to  which  these  people  lied  and 
evidence  appeared  to  be  indisputable  that  the  disease  -pread  by 
contagion  in  certain  localities  within  the  city  or  its  environ-,  and  the 
lusion  was  arrived   at   that   the  contaL'i"n  could   not   e\M   in  the 
country,  but  originated  de  novo  in  certain  localities  in  the  cities,  as  a 
result  OI  peculiar  atmospheric  and  local  conditions.      It  v  rvcd 

that  the  nuns  of  the  urcneral  hospital  who  were  thrown  into  frequent 
and  direct  contact  with  the  sick  escaped  t lie  disease,  while  in  the 
valescent  hospital  the  president,  the  head  apothecary  and  the  superin- 
tendent.  none  of  whom  had  ever  entered  the  rooms  of  the  sick. 
who  had  taken  every  precaution  not  to  communicate  with  the  sick 
nor  with   anything  De&ngjng  to  them,  all   fell  ill.     Of  course,  now 
that  we  know  that  natural  or  nonexperimental  yellow  fever  can  only 
be  contracted  through  the  bite  of  a  contaminated  mosquito,   it    is 
quite  clear  that  the  presence  or  absence  of  the  disease  in  certain  locali- 
ties means  simply  the  presence  or  absence  of  contaminate!  1   moB- 
quitos.     As  we  view  the  subject  now,  the  yellow  fever  mosquito 
brought  to  Spanish  ports  by  vessels  coming  from  Habana,  and  be  in;; 
a  house  mosquito,  it  multiplied  in  those  cities  during  tin4  warm  se, 
It  was  then  at  hand  to  receive  and  transmit  the  infecti<  -us  a-ent  when- 
ever it  encountered  cases  of  the  disease,  and  these  were  frequent  ly  im- 
ported.    Upon  the  appearance  of  frost  the  mosquito  went  into  hiber- 
nation and  the  epidemic  promptly  ceased.     As  the  insect  was  an  im- 
ported one  it  was  not  present  in  the  country  districts,  consequently 
there  was  no  extension  of  the  disease  from  patients  treated  1 1 
in  the  cities  the  epidemic  could  only  spread  where  the  proper  mos- 
quito chanced  to  be  present.     The  introduction  of  the  mosquito  alone 
can  have  no  ill  effect  unless  it  has  previouslv  bitten  yellow  fever  pa- 
tients, and  in  like  manner,  sufferers  from  yellow  fever  are  absolut  ely 
harmless  to  others  unless  they  are  bitten  by  the  proper  mosquit  o. 

As  Dr.  Howard,  no  doubt,  told  you  last  year,  the  female  mosquito 
at  certain  periods  in  her  existence  experiences  a  physiologic  need 
for  blood.     The  hemoglobin  of  the  blood  seems  necessary  for  the 
maturation  of  her  ovums,  and  she  will  not  deposit  her  eggs  until  she 
has  obtained  a  meal  of  blood.     The  male  insect  can  not   transmit 
yellow  fever,  because,  having  no  need  for  it,  he  never  sucks  blood. 
and  while  his  proboscis  will  provide  him  with  fruit  juices,  it  will  not 
penetrate  the  animal  skin.     The  mysterious  movement  s  of  the  disease, 
passing  from  house  to  house,  even  at  times  when  there  had  been  no 
communication  between  the  inhabitants;  the  remarkable  immunity 
enjoyed  by  some  groups  of  persons  who  were  equally  and  full 
orach  exposed  as  others  who  were  decimated  by  its  ravages;  t 
as  well  as  the  peculiar  way  hi  which  the  infection  clung  to  dwell 
and  ships,  invested  it  with  a  mystery  that  puzzled  physician 
centuries,  and  remained  totally  unexplained  until  the  demonstration 
of  the  mosquito  theory  within  the  past  five  years.     Even  to-d,, 
our  own  country,  where  the  results  upon  which  it  is  based  were  first 


YELLOW   FEVER.  197 

published,  the  mosquito  theory  of  the  transmission  of  yellow  fever 
still  has  many  opponents,  and  some  of  its  supposed  friends  are  very 
weak-kneed  and  seem  still  to  be  looking  -for  evidence  that  would 
justify  them  in  deserting  it.  It  is  painful  to  read,  in  one  of  our  most 
prominent  and  influential  daily  newspapers,  the  letters  emanating 
from  a  well-known  writer  upon  the  subject  of  yellow  fever,  who  a 
few  years  ago  was  looked  up  to  as  an  authority  and  wrote  for 
standard  professional  works,  but  who  is  now  damaging  his  own 
reputation  and  retarding  progress  by  asserting  that  the  mosquito  is 
not  the  sole  medium  for  the  transmission  of  this  disease.  It  does  not 
seem  to  have  occurred  to  this  widely  known  and  most  interesting 
writer  that  the  burden  of  proof  rests  upon  him,  and  that  he  should 
either  remain  silent  or  be  prepared  to  prove  by  actual  demonstration 
that  there  is  some  foundation  for  his  claim.  I  take  the  liberty  here 
to  suggest  to  the  paper  in  whose  interest  this  writer  was  sent  to  Cuba, 
that  it  could  hardly  invest  a  few  hundred  dollars  more  profitably  than 
to  enable  this  gentleman  to  furnish  the  necessary  evidence  in  support 
of  his  statements,  if  such  evidence  is  obtainable,  as  it  certainly  should 
be  if  his  assertions  are  well  founded.  Who  would  think  to-day  of  1 
advancing  the  old  theory  that  malarial  infection  is  contracted  in  any 
other  way  than  through  the  bite  of  the  mosquito  ?  No  one  who  is 
familiar  with  modern  ideas  on  parasitology  would  entertain  the  idea 
for  a  moment,  and  there  is  no  more  ground  for  assuming  that  yellow 
fever  is  transmitted  in  any  other  way  than  there  was  formerly  for 
entertaining  that  opinion  in  regard  to  malaria.  In  your  own  State 
during  the  last  two  years  you  have  had  abundant  evidence  of  the 
power  of  measures,  based  upon  the  mosquito  theory  alone,  to  suppress 
this  disease,  even  when  that  theory  met  only  half-hearted  acceptance.  \ 
Do  not  understand  me  as  intending  to  reproach  those  hesitating 
nonbelievers  who  were  so  slow  to  move ;  on  the  contrary,  I  sympathize 
with  them  and  with  their  refusal  to  conform  their  ideas  to  all  the 
new  theories  that  were  being  constantly  advanced,  then  denied,  con- 
tested, and  recontested  with  every  reappearance  of  the  disease. 

But  let  us  return  again  to  the  scenes  enacted,  and  the  conditions 
found,  where  the  disease  has  prevailed  in  the  past.  Dr.  O'Halloran, 
in  summing  up  after  studying  the  epidemic  at  Barcelona,  calls  atten- 
tion to  the  House  of  Charity,  a  clean,  well-ventilated  building  in  the 
noninfected  part  of  the  city,  and  which  was  occupied  by  more  than 
1,100  persons  during  the  height  of  the  epidemic.  These  persons,  men, 
women,  and  children,  went  out  daily  into  various  parts  of  the  city, 
some  visited  the  sick  and  entered  the  houses  of  the  dying  and  the 
dead.  Among  all  this  number,  only  2  contracted  the  disease.  These 
were  treated  in  theSeminario  Hospital,  where  1  recovered  and  the  other 
died.  The  one  that  recovered  was  at  once  returned  to  the  House  of 
Charity,  where  she  mingled  with  the  other  inmates ;  still  none  of  them 
was  affected.  He  then  says: 

The  foregoing  is  a  true  report,  and  may  be  regarded  as  an  important  one.  Had  the 
House  of  Charity  been  situated  in  the  eastern  extremity  of  Barcelona,  or  in  Barceloneta, 
where  the  epidemic  cause  existed  to  a  high  degree,  the  destruction  would  have  been 
in  all  probability  great;  but  as  the  cause  did  not  extend,  or  only  in  a  very  inferior 
degree,  to  that  part  of  the  city  in  which  the  House  of  Charity  stands,  the  cause  of  the 
nonpropagation  of  the  malady  is  easily  accounted  for.  This  case  strongly  tends  to 
prove  that  the  yellow  fever  will  not  multiply  except  where  an  epidemic  cause  exists 
in  force;  and  it  moreover  proved  that  the  disease  is  not  contagious. 


198  \TP.. 

Further  on.  in  speaking  of  the  Ca-a  Miserecordiji.  or  House  of  Vity. 
he  states: 

The  building  is  low,  but  the  apartments  are  spacious  and  well  ventilated.  It  con- 
tained  150  girls  during  the  rage  ot  the  epidemic.  The  nuns  who  i<  :K  h  them  are  •_'  i  in 
numl  -  maintain  themselves  by  washing,  ironing.  and  other  similar  modes 

of  occupation.    They  employ  women  to  traverse  the  city  from  house  to  house  to  ]>n> 
cure  needlework,  etc.    These  women  went  to  all  parts  of  the  city;  they  communJ 
indiscriminately  with  the  inhabitants,  and  they  were  not  affected  by  the  disea.^ 
did  the  nuns  or  girls  suffer  by  communicating  with  them.    This  is  a  singular  fact,  and 
a  strong  one.    1  1  appears  strange  that  a  disease  which  was  said  t.>  ha\e  I.een  im; 
from  Habana  into  Barcelona,  from  Barcelona  to  Intosa,  and  from  thence  to 
.inenza,  Malaga.  etc.,  c«>nld  n<»t  be  introduced  into  the  House  of  I'ity  th 
numerous  channels  of  communication. 

Again,  speaking  of  the  House  of  Correction,  a  thiee-Mory  >t«»nr 
building.  in  which  were  located  100  females  during  the  epidemic 
season,  lie  asserts: 

Nine  of  them  were  attacked  with  the  reigning  malady;  4  of  them  had  been  recently 
admitted  as  having  committed  some  irregularity  in  rickly  Barreloneta.     Tin-;. 
all  removed  to  the  Seminario  Hospital,  where  -1  died;  the  remaining  '».  when  cured, 
returned  to  the  House  of  Correction;  they  communicated  freely  with  the  other 
no  disease  ensued.    This  house  was  visited  daily  by  some  of  the  female  inhabit. 
the  city,  who,  through  charity,  brought  eatables,  etc.,  but  without  detriment  to  the 
inmates. 

Hao!  this  been  a  contagious  malady,  the  persons  who  r<  'turned  to 
the  House  of  Correction  after  being  cured  in  the  Seminario  Hospital. 
which  was  then  the  seat  of  pestilence  and  of  death,  and  to  which 
hundreds  were  sent  to  die,  eould  scarcely  have  failed  of  communi- 
cating the  disease  to  the  numerous  females  who  had  intercourse  with 
them  at  all  hours  of  the  clay. 

Of  50  persons  who  were  constantly  employed  burying  the  dead. 
only  2  died,  although  they  communicated  freely  with  the  inhabitants 
of  the  city  in  the  nighttime. 

Later  he  mentions  the  lazaretto  called  Marine,  a  mile  to  the  east  of 
Barcelona  and  within  150  yards  of  the  sea.  It  was  opened  for  the 
si<  k  on  August  7;  79  sick  were  admitted,  of  whom  58  died  :  :>J  net 
were  employed  in  various  duties  of  the  establishment  as  doctors, 
friars,  servants,  and  washerwomen,  and  not  one  of  them  took  the 
disease.  Of  the  above  number,  6  were  employed  in  burying  the 
dead,  and  3  in  washing  the  bedding.  After  this  establishment  was 
broken  up,  5  women  remained  in  it,  employed  in  washing  the  bedding 
of  the  Seminario  Hospital,  but  without  being  affected  by  the  disease. 

In  his  conclusions,  he  finally  observes  in  discussing  the  epidemic  : 

Its  fatal  and  malignant  nature  in  unventilated  places;  the  exemption  of  parts  «i  the 
city  from  its  influence,  when  no  precautions  were  taken;  the  M<  •kenin.u  of  persons 
who  observed  the  strictest  seclusion;  the  sudden  impression  of  contaminated  air  on 
persons  recently  from  the  country,  without  communication  with  the  inhabitants  of 
the  city;  the  greater  exemption  of  nurses  and  other  attendants  on  the  sick  from  the 
disease,  than  those  who  were  simply  exposed  to  the  contaminated  air  of  sickly  houses; 
the  almost  absolute  exemption  of  washers  of  bedding,  clothes,  etc.,  which  had  recent  1  y 
been  used  by  the  sick;  the  circumstance  of  the  attendants  in  the  hospitals  and  laza- 
rettos having  generally  escaped  the  impression  of  the  malady;  the  impossibility  <-f 
diffusing  the  disease  in  the  country,  where  no  epidemic  cause  existed;  and,  finally, 
eath 


the  death  of  some  hundreds  of  persons  who  communicated  with  Ban  .  i 

sickened  in  the  neighboring  villages  and  country  houses  without  a  solitary  in  • 
of  its  affecting  the  most  assiduous  of  its  attendants,  however  circumstanced,  are  ascer- 
tained facts  and  convincing  proofs  of  the  noncontagious  nature  of  the  yellow  fever. 

The  evidence  that  Dr.  O'llalloran  offers  in  support  of  his  coin 
tion  that  yellow  fever  is  not  contagious  is  most  ronelusiv«».     After 


YELLOW    FEVER.  199 

reciting  the  appearances  found  upon  dissecting  the  bodies  of  those 
who  had  died  of  the  disease,  he  publishes  a  letter  written  by  Dr. 
Salvador  Campmany  during  the  following  year.  Dr.  Campmany  was 
in  charge  of  the  Virreina  Hospital  at  Barcelona  during  the  outbreak 
of  1821,  when,  between  September  1  and  December  20,  this  hospital 
handled  the  bodies  of  no  less  than  8,649  persons  dead  of  yellow  fever. 
O'Halloran  states  that  Dr.  Campmany  was  at  first  of  the  belief  that 
the  disease  was  contagious,  and  when  he  began  to  take  care  of  the 
sick  he  wore  an  oilcloth  dress.  The  letter  is  so  interesting  that  I 
shall  give  you  the  last  paragraph  verbatim. 

The  above  sketch  does  not  afford  grounds  for  argument  as  to  the  contagious  or  non- 
contagious  nature  of  the  disease.  I  shall  only  state  that  out  of  30  persons  of  all  descrip- 
tions who  were  destined  to  assist  the  sick  not  one  took  the  disorder.  The  nurses  con- 
tinually communicated  with  the  sick.  When  delirious  patients  escaped  from  their 
beds  the  assistants  had  to  take  them  on  their  shoulders  and  replace  them  in  their 
respective  quarters.  On  the  opening  of  the  bodies  the  anatomists,  in  my  presence, 
involuntarily  cut  their  fingers  and  hands,  and  not  one  was  inoculated  with  the  yellow 
fever.  When  the  gravediggers  carried  the  dead  bodies  to  the  church  yard  they  had  to 
handle  them  a  great  deal  before  throwing  them  into  the  pit,  and  not  one  suffered  in 
his  health.  In  short,  not  an  individual  employed  in  the  lazaretto  either  took  the 
disorder  or  was  infected  by  those  who  were  sick  of  the  yellow  fever. 

One  could  scarcely  desire  more  complete  confirmation  than  this  of 
the  subsequent  demonstration,  almost  60  years  later,  by  the  army 
board,  of  the  noninfectiousness  of  the  clothing,  bedding,  and  dejecta 
of  yellow  fever  patients. 

These  were  the  opinions  in  1823  of  an  observer  who  had  seen  and 
himself  suffered  from  yellow  fever  in  the  West  Indies  some  years 
before.  Others,  however,  who  were  equally  qualified  to  observe, 
insisted,  and  advanced  evidence  to  show,  that  the  disease  was 
imported  and  that  it  was  contagious.  In  short,  the  same  differences 
of  opinion  and  the  same  dissensions  among  the  highest  authorities  in 
regard  to  this  disease  prevailed  then  as  before  and  since,  even  to  the 
present  day.  O'Halloran  states  that  the  disease  was  not  declared  to 
be  the  American  yellow  fever  until  August  14,  1821;  that  in  April  a 
fleet  of  52  vessels  sailed  from  Habana  for  various  Spanish  ports,  20  of 
them  for  Barcelona.  Cases  of  yellow  fever  occurred  on  some  of  these 
vessels  after  their  arrival  in  Spain,  but  for  commercial  reasons  every 
effort  was  made  to  conceal  them  and  deny  their  real  nature.  Many 
of  the  sailors  on  the  infected  vessels  were,  of  course,  immune,  and  of 
those  who  were  susceptible  the  larger  number  had  suffered  attacks 
during  the  voyage,  so  that  while  they  were  lying  in  the  Spanish  har- 
bors the  first  persons  to  become  infected  were  those  who  visited  the 
ships  for  the  purpose  of  unloading,  making  repairs,  etc.  Some  of 
these  vessels  lay  at  Barcelona  early  in  June,  and  we  are  told  that 
during  this  month  "the  bilious  remittent  or  gastric  fever  was  common, 
and  ultimately  predominated  in  so  high  a  degree  as  in  a  manner  to 
supersede  all  other  diseases;  and  that  during  the  month  of  July  the 
bilious  remittent  fever,  with  hemorrhagic  affection,  was  common  and 
obstinate."  The  following  sentence,  quoted  verbatim,  is  of  much 
interest  to  us  at  present : 

It  is  worthy  of  remark  that  during  this  month  (July)  the  flies  and  mosquitoes  were 
infinitely  multiplied. 

How  well  this  reminds  us  that  the  same  unusual  prevalence  of 
mosquitoes  during  an  epidemic  of  yellow  fever  has  been  noted  by  a 
number  of  American  physicians,  including  Dr.  Rush,  at  Philadelphia, 


200 

in  1797  and  1805;  Dr.  Vaughan,  at  Wilmington.  1VL.  in  1802;  Or. 
Weightmann,  at  St.  Aui:iistine.  Kla..  in  ls:;<i;  Dr.  \Yood.  at  (Vnter- 
ville,  and  Dr.  Beyrenheiat,  at  Hil«>\i.  Mi>^..  as  well  as  Dr.  Barton,  at 
Clinton,  La.,  an.l  hr.  Ho\\ler,  at  New  Orleans,  all  in  is">:>.  \\'hat 
interest  these  ol)-n-\  at  ions  add  to  the  now  well-known  mosquito 
theory  of  tlu'  u  ..»n  of  the  disease,  and  how  well  do  modern 

neiices  and  knowledge  add  confirmation  to  Sydenham's  theory 
that  certain  diseases  resulted  from  an  ' 'epidemic  constitution  of  the 
atmosphere. " 

1  would  like  here  to  call  your  attention  to  some  statements  made 
by  a  well-known  Galveston  physician  in  1876.  I>r.  ( Ireensvillf 
ifewell,  at  that  time  a  member  of  the  Galveston  Medical  Society  and 
professor  of  surgery  in  the  Texas  Medical  College,  wrote  of  yellow 
fever,  of  which  he  was  a  wonderfully  close  student,  as  folio v. 

Its  history  shows  that  no  ship,  however  filthy,  can  develop  it  while  it  n  mains  out 
of  its  endemic  or  epidemic  influence.     No  heat  or  moisture  can  alone  pro 
we  would  have  it  as  often  in  the  East  Indies  as  in  the  West  Indies,  an<l  if  tin- 
in  the  East  Indies  were  the  same  as  in  the  West  Indies  it  would  be  intr<><!  . 
as  well  as  in  the  Y\  ••-;  Indies,  by  ships.    Hence  there  must  be  some  cause,  8]< 
and  sui  generis,  that  produces  it.    This  cause,  I  have  assumed,  is  animalcular  or  fun- 
gptic,  and  partakes  of  the  nature  of  the  grasshoppers  of  Egypt  and  the  western  prai- 
ries, or  the  smut  in  cereals;  but  these  are  too  small  to  be  observed  with  any  instruments 
we  now  have,  and  have  so  far  eluded  demonstration;  but  if  we  compare  the  eff<  < 
heat  and  cold  on  gnats  and  mosquitos  with  yellow  fever,  it  will  not  bo  dilli.  uli  to 
believe  it  is  of  the  same  nature,  as  it  is  controlled  by  the  same  natural  laws.1 

So  far  as  I  know,  Dr.  Greensyille  Dowell  was  the  first  even  indi- 
rectly to  incriminate  the  mosquito  by  pointing  out  the  fact  that  it 
is  governed  by  the  same  natural  laws  as  yellow  fever.  And  live 
years  after,  in  1881,  Dr.  Finlay  enunciated  his  theory  that  the  dis- 
ease was  transmitted  by  the  mosquito,  but  his  theory  was  not  pr 
until  19  years  later. 

O'Halloran's  observation  that  bilious  remittent  fevers  prevailed  for 
two  months  prior  to  the  appearance  of  yellow  fever  has  been  dupli- 
cated in  the  United  States  hundreds  of  times,  and  we  are  forced  to  the 
conclusion  that  there  must  be  some  relationship  between  bilious  remit- 
tent and  yellow  fever.  O'Halloran  thought  tnat  these  bilious  remit- 
tent fevers  were  of  local  origin  and  that  they  gradually  merged  int<> 
yellow  fever.  The  same  opinion  has  been  held  by  many  in  our  «.\vn 
country,  but  this  has  been  offset  by  evidence,  on  the  other  hand,  that 
bilious  remittent  fever  was  undoubtedly  imported  from  the  Tropies, 
and  was  simply  a  milder  form  of  yellow  fever.  The  truth  is  that 
practically  all  such  cases  were  genuine  yellow  fever  that  were  not 
recognized  because  of  the  absence  of  black  vomit,  which  has  been 
erroneously  regarded  as  a  necessary  symptom.  In  the  work  of  the 
Army  commission  14  cases  of  experimental  yellow  fever  were  pro- 
duced by  means  of  the  mosquito,  and  some  of  them  were  severe,  hut 
black  vomit  was  not  present  in  a  single  instance.  This  led  some 
persons  to  the  conclusion  that  cases  produced  by  only  one  or  two 
mosquitos  were  necessarily  mild,  hut  the  experience  of  Dr.  (iuiteras 
in  August,  1901,  proved  the  contrary.  Out  of  seven  cases  that  he 
produced  by  the  bites  of  one  or  two  mosquitoes,  three  died  with 
black  vomit. 

I  have  purposely  cited  from  Dr.  O'Halloran's  account  of  the  epi- 
demic at  Barcelona  in  order  to  show  that  other  careful  observers, 

i  Yellow  Fever  and  Malarial  Diieases,  by  Oreensvllle  Dowell,  M.  D.    Philadelphia:  1876,  p.  13. 


YELLOW   FEVER.  201 

working  in  other  fields,  have  recorded  the  same  observations  and  the 
same  opinions  as  the  older  American  physicians. 

The  literature  of  yellow  fever  in  the  United  States  shows  that  in 
nearly  every  outbreak  a  number  of  cases,  usually  the  first  ones  to 
occur,  have  escaped  recognition.  This  has  happened  from  the  time 
of  Rush  until  to-day,  and  has  been  due  to  (1)  the  comparative  mild- 
ness of  the  cases,  which  led  to  the  diagnosis  of  "bilious  remittent 
fever;"  (2)  the  dread  on  the  part  of  the  physician  attending  these 
cases  to  assume  the  responsibility  for  diagnosing  the  first  case  of 
yellow  fever,  because,  in  the  event  that  black  vomit  did  not  super- 
vene, the  correctness  of  the  diagnosis  would  be  called  into  question, 
and  the  physician  would  be  branded  an  enemy  to  the  community. 
The  Eleventh  Annual  Report  of  the  Florida  State  Board  of  Health, 
published  in  1900,  furnishes  an  admirable  illustration  wherein  it  is 
shown  that  in  the  outbreak  at  Key  West  in  August,  1899,  there  were 
already  11  cases  unrecognized  in  the  town  before  a  single  one  was 
correctly  diagnosed.  Is  it  any  wonder,  then,  that  under  such  cir- 
cumstances the  disease  was  able  to  gain  a  firm  foothold  ?  The  occur- 
rence of  a  number  of  cases  of  the  so-called  "  bilious  remittent  fever," 
of  short  duration,  should  always  excite  suspicion,  for  such  cases, 
when  found  in  groups,  are  almost  invariably  cases  of  genuine  yellow 
fever.  At  the  present  day  nothing  less  than  the  absolute  demonstra- 
tion by  an  experienced  observer  of  the  presence  in  the  blood  of 
malarial  parasites  or  spirillums  would  justify  any  other  diagnosis 
than  yellow  fever;  and  even  if  they  were  shown  to  be  cases  of  malarial 
or  relapsing  fever,  modern  scientific  medicine  requires  that,  in  the 
case  of  the  former  at  least,  the  patients  should  be  rigidly  protected 
against  the  bites  of  mosquitoes,  since  we  know  that  malaria,  like 
yellow  fever,  can  be  transmitted  in  no  other  way  than  through  the 
bite  of  that  insect,  if  we  except  experimental  inoculation.  In  the  case 
of  relapsing  fever,  of  the  manner  of  transmission  of  which  we  know 
absolutely  nothing,  it  would  be  wise  to  take  the  same  precaution. 

The  epidemics  that  have  ravaged  the  city  of  Philadelphia  have 
been  so  graphically  described  by  Rush  and  later  by  La  Roche  that 
one  is  apt  to  conclude  that  the  only  serious  outbreaks  this  country 
has  experienced  were  those  occurring  at  Philadelphia,  New  Orleans, 
and  one  or  two  other  seaports.  It  is  only  when  we  search  the  litera- 
ture of  this  disease,  that  we  can  appreciate  the  general  devastation 
and  terror  created  by  it,  and  the  enormous  losses  sustained  by  the 
communities  it  has  visited.  In  a  treatise  on  yellow  fever  by  Dr. 
Samuel  Brown,  of  Boston,  which  was  published  in  1800,  he  says  in 
speaking  of  the  disease :  "This  is  a  foe  against  which  neither  ramparts 
nor  intrenchments  afford  any  security:  'It  wasteth  at  noonday;'  and 
every  principal  town  throughout  the  United  States  exhibits  recent 
and  mournful  testimonials  of  its  ravages.  We  will  not  enter  upon  a 
particular  detail  of  the  distresses  which  Philadelphia,  New  York, 
Boston,  and  other  commercial  places  have  experienced;  the  tale  of 
woe  would  be  too  afflictive  for  even  the  dullest  sensibility  to  bear 
and  the  feelings  of  humanity  would  be  agonized  to  overexcitement." 

In  order  to  show  the  manner  in  which  yellow  fever  invades  a  sea- 
port town,  and  the  mystery  attendant  upon  its  appearance  and 
spread,  I  will  quote  from  the  report  of  the  committee  of  medioal  men 
appointed  to  investigate  the  outbreak  that  occurred  at  Mobile,  Ala., 
in  1819.  After  giving  in  detail  the  condition  of  the  wharves  and 


202  DW    WW1  K. 

docks,  the  direction  of  tlu-  prevailing  winds,  and  the  dourer  of  tem- 
perature and  moi>ture.  they  state  that  during  the  previous  winter, 
spring,  and  summer  up  to  .Inly  1.  the  city  was  healthy.  In  the 
latter  part  of  July  a  number  it  eases  of  bilious  fever  occurred 

among  persons  unaccustomed  to  the  climate,  and  some  of  a  more 
(|ue>tionahle    character;  several  persons  employed  as  workmen   in 
filling  up  one  of  the  new  wharves  were  taken  violently  ill.  and 
after  a  short  illne—  of  two  or  three  days.     About  the  same  time  t\vo 

usually  employed  ahout   Daimhin  Street  Wharf  we: 
m  like  manner,  and  died  after  a  short  illness.    A  number  of  carpel 
and  sailors  employed  about  the  wharf,  and  who  were  much  on  1 
the  schooner  Sally,  filled  with  stagnant  water,  and  about  the  steam 
sawmill,  where  there  was  a  pond  of  like  offensive  water. 
with  violent  fevers,  and  several  of  them  died.     The  ph;  who 

attended  these  persons  died,  but  it  is  stated  that  one  of  them.  Dr. 
Lawton,  spoke  of  them  as  cases  of  malignant  fever.     An  engineer 
at  work  on  a  steamboat  at  the  same  wharf  died  soon  after.  hU  (lineal 
lasting  5  days.     A  man  who  attended  him.  and  a  servant  boy  living 
in  the  same  house,  were  taken  down  with  a  similar  fever,  and  died 
on  the  third  and  fourth  days.     All  these  persons  died  with  Mack 
vomit,  and  were  declared  by  the  attending  physicians  to  be  cas. 
yellow  fever.     At  about  the  same  time  otner  fatal  cases  occurred 
among  persons  whose  time  was  spent  about  the  ri\  er  and  wi 
stores  in  that  neighborhood.     Within  a  few  days  after  the  prevail 
of  yellow  fever  was  known  an  exodus  took  place,  and  the  population 
became  reduced  from  1,300  in  July  to  500.     Of  these,  133,  or  over 
25  per  cent,  died/' 

The  report  states  that  the  suburbs  of  the  town,  at  no  greater  dis- 
tance than  a  mile  from  the  river,  were  as  healthy  during  the  prevalem-e 
of  the  fever  as  more  distant  parts  of  the  country;  and  the  disease  was 
not  known  to  be  communicated,  in  any  instance,  to  persons  out  of  the 
town  by  the  removal  of  and  attendance  upon  the  sick.     Hence,  it  was 
concluded  that  the  disease  was  only  communicable  in  the  atmosphere 
in  which  it  originated,  and  even  then  some  other  cause,  not  under- 
stood, appeared  to  be  necessary,  because  "a  number  of  persons  fre- 
quently in  the  room  with  the  sick,  dying,  and  dead,  in  circum^ta 
of  the  greatest  exposure,  never  took  the  fever."     It  is  further  rem;i 
that  Natchez  ana  other  ports  on  the  Mississippi  below  suffered  heavily, 
and  practically  every  seaport  on  the  Atlantic  and  Gulf  coasts  npp< 
to  have  suffered  more  or  less  that  summer  from  yellow  fever.     It  is 
very  interesting  to  note  how  the  disease  almost  invariably  first  made 
;>pearance  in  the  vicinity  <•!  wharves  and  shipping,  in  parts  of  the 
town  where  surface  drainage  is  usually  more  or  less  detective,  and 
decaying  wood  and  vegetable  refuse  are  necessarily  present . 
were* the  only  special  conditions  found  to  prevail  m  these  localit  i. 
was  quite  generally  conceded  that  to  them  t  he  disease  owed  its  on 
When  vessels  with  yellow  fever  on  board  arrived  in  p«>rt,  ell- 
made  to  conceal  the  nature  of  the  disease,  and  by  fa.  hen 
patient  <  were  buried  at  sea,  or  by  burial  at  night  where  death  occurred 
m  port,  many  cases  are  known  to  have  been  concealed.     Again,  a 
vessel  with  an  immune  crew,  but  infected  mosquitoes  on  board,  would 
infect*  persons  from  shore  who  visited  the  ship  for  various  purposes, 
yet,  there  being  no  sickness  on  the  vessel,  she  \\a-  relieved  of  su-pi 
and  the  disease  was  assumed  to  be  of  local  origin.     Cases  resembling 


YELLOW   FEVER.  203 

yellow  fever,  but  without  black  vomit,  were  called  bilious  fever,  and 
under  this  guise,  aided  by  the  occasional  concealment  of  an  undoubted 
case,  the  disease  frequently  escaped  detection  for  weeks  and  months. 

In  the  description  of  the  epidemic  at  Baltimore,  also  in  1819,  as 
observed  by  various  practicing  physicians,  we  find  many  statements 
that  must  now  be  regarded  with  special  interest.  For  instance,  it  was 
conceded  by  all  that  the  first  cases  appeared  at  Fell's  Point,  where  the 
principal  docks  and  wharves  were  located.  One  observer  states  that 
the  disease  never  originated  more  than  two  or  three  hundred  yards 
from  the  water,  and  it  was  six  weeks  from  the  commencement  before 
the  disease  had  spread  much  more  than  100  yards  from  the  place  of 
origin.  The  transmission  of  the  contagion  was  rightfully  attributed 
to  some  unknown  agent  present  in  the  atmosphere,  for  in  speaking  of 
the  infection  it  is  said,  "upon  this  ground,  then,  it  may  be  asserted  that 
some  matter  which  was  foreign  to  the  natural  composition  in  the  air 
of  this  place  floated  about  with  it  at  this  time.  Some  portion  of 
whatever  this  air  contained  was  therefore  of  necessity  breathed  or 
swallowed  by  the  people  who  came  within  its  limits.  And  the 
properties  of  the  foreign  matter  in  this  air  must  be  decided  upon  by 
the  effects  which  it  has  had  on  those  who  receive  it  into  their  habits.'' 
We  have  only  to  add  the  mosquito  now,  and  the  general  truth  of  the 
above  statements  becomes  manifest.  And  with  the  mosquito  we 
necessarily  include  the  insect's  bite  as  an  additional  and  at  that  time 
unknown  avenue  of  entrance  for  disease.  Conceding  this,  how  easily 
one  can  explain  the  first  appearance  and  prevalence  of  the  disease  in 
the  localities  where  the  conditions  are  favorable  for  the  multiplication 
of  mosquitoes,  viz,  in  the  low-lying  and  generally  poorly  drained 
districts  in  the  vicinity  of  the  wharves  and  shipping.  When  we  con- 
sider further  that  the  mosquito  that  transmits  yellow  fever  is  a  tropic 
and  subtropic  insect  and  that,  practically  speaking,  it  is  not  found 
north  of  Mason  and  Dixon's  line,  it  then  becomes  absolutely  clear  that 
yellow  fever  in  epidemic  form  can  be  introduced  into  that  section 
only  when  the  presence  of  high  atmospheric  temperature  and  moisture 
afford  conditions  favorable  for  the  propagation  of  this  insect.  But 
the  yellow-fever  mosquito  is  a  tropic  insect,  and  yellow  fever  is  a  tropic 
disease;  it  follows,  therefore,  that,  given  the  proper  conditions  as  to 
temperature  and  moisture,  there  must  have  been  introduced  at  that 
time  both  the  proper  insect  and  cases  of  the  disease.  These  must 
necessarily  have  come  originally  from  infected  localities  within  or  near 
the  Tropics. 

In  the  days  when  yellow  fever  prevailed  in  our  northern  seaports 
outbreaks  invariably  followed  the  arrival  of  one  or  more  vessels 
from  Habana  or  some  other  infected  port,  but  the  interval  elapsing 
between  the  entry  of  the  vessel  and  the  recognition  of  the  disease 
was  so  long  and  the  manner  of  extension  of  the  disease  was  so  mys- 
terious that  it  became  impossible  to  trace  the  connection  between  the 
one  and  the  other.  Let  us  suppose,  for  example,  in  the  month  of 
July,  at  a  time  when  yellow  fever  prevailed  and  before  the  days  of 
rigid  quarantine,  a  sailing  vessel  lying  at  Habana  and  bound  for 
Baltimore.  She  is  tied  up  at  a  dock,  and  numbers  of  the  yellow- 
fever  mosquitoes,  which  are  the  prevailing  house  mosquito  at  Habana, 
fly  aboard.  They  deposit  their  eggs  in  open  casks,  pitchers,  or  other 
receptacles  containing  fresh  water  exposed  to  the  air.  The  crew  are 
immune  with  one  exception,  and  this  man  is  taken  sick  three  or  four 


204  YELLuu 

da\>  uut    from  Habana  on  the  journey  northward.      He  has  yellow 
fever,  but    his    temperature  is  only  moderately  High,  ami    although 
he  is  deeply  jaundiced  there  is  no  black  vomit.     The  captain  ii 
the  case  is  one  of  bilious  remittent  fever  and  not  yellow  fever.     \ 
onecould  quest  ion  his  statement .  because  even  the  best  physicians  \\ere 
unable  at  that  time  to  draw  the  line  between  yellow  fever  and  malarial 
fever,  and  it  is  not  always  easy  to  do  it  to-day.     The  hypothei  i 
genuine  though  unrecognized  yell  i-  hit  ten  by  a  iiumherMf  tnoa- 

qmtoes  during  the  first  t  hree  days  of  his  fever,  bu1  DO  one  is  aware  of  ii. 
MP  \\Miild  attach  any  importance  to  it  if  they  knew.      In  two  weeks 
the  patient  is  practically  well,  and  in  another  week  «>r  t  WM  the  \ 
arrives  in  port   with  a  clean  bill  of  health.     There  i-  no  sickne 
board,  she  is  in  fairly  good  condition,  and  ties  up  to  the  dock  in 
Baltimore — say  25  or  30  days  after  leaving  Habana,  and  with  several 
infected  mosquitoes  on  board. 

Perhaps  these  mosquitoes  are  disturbed  by  the  unloading  Mf 
the  ship  or  cleaning  of  the  cabins,  and  they  may  lly  onto  another 
ship  tied  up  at  the  same  wharf  or  travel  along  the  wharf  to  a  watch- 
man's house  or  some  other  dwelling  in  the  immediate  vicinity.  The 
first  cases  of  the  outbreak  may  appear  on  the  other  ship  tied  up  at 
the  dock,  and  this  latter  vessel  may  have  come  from  Kui-Mpe  and 
be  in  rather  foul  condition.  The  infection  in  that  case  would  he 
attributed  to  the  foul  air  generated  by  the  action  of  a  hot  atmosphere 
upon  the  decomposing  matter  present  in  her  hold.  The  next 
may  appear  in  some  one  sleeping  or  employed  on  the  dock  nr  MM  a 
neighboring  vessel.  In  the  month  of  August  conditions  would  he 
favorable  for  the  propagation  of  mosquitoes,  and  in  addition  to  those 
hatched  out  on  the  trip  from  Habana  another  brood  will  soon  have 
appeared  on  shore.  Tne  mosquito  may  also  have  been  introduced 
by  other  vessels  earlier  in  the  season,  and  the  conditions  "\\ill  then 
be  suitable  for  a  further  extension.  The  continuance  of  the  out- 
break  necessarily  depends  on  the  coming  together  of  the  imported 
mosquitoes  and  cases  of  yellow  fever  in  the  first  three  days  of  the 
disease;  consequently  in  numerous  instances  only  one  or  two  •  • 
occur,  and  none  follows  unless  fresh  cases  are  introduced  by  other 
vessels  from  infected  ports.  The  frequency  of  the  occurrence 
cases  of  bilious  remittent  fever  in  American  ports  during  the  la-t 
century  shows  that  during  the  early  part  at  least  yellmv  fever  waa 
being  constantly  imported,  though  it  onlv  occasionally  assumed 
epidemic  proportions.  Let  us  suppose  that  the  vessel  lea  vim:  1  lahana 
sailed  for  New  Orleans,  Mobile,  or  Galyeston,  instead  of  Baltim<»n >. 
Here  the  case  will  be  different,  because  in  these  places  the  condit  ion- 
are  favorable  for  the  propagation  of  the  vellow-fever  mo«juito 
throughout  the  greater  part  of  the  year,  and  the  introduction 
single  case  might  prove  sufficient  to  fight  up  an  epidemic.  l>< •< -au-e  t  he 
proper  mosquito  is  at  nearly  all  times  present  in  the  house-  m  ahun- 
dance.  Frequent  severe  outbreaks  have  occurred  at  New  Or  lean- 
until  a  large  part  of  the  population  had  become  immune,  and  tin.., 
were  nonimmunes  and  could  afford  it  habitually  left  the  city 
during  the  warm  season.  Among  the  few  who  remained  and  chanced 
to  be  bitten  by  the  proper  infected  mosquitoes,  cases  would  occur 
from  time  to  time  as  bilious  fever,  often  suspected  to  be  yellow 
fever,  hut  for  reasons  of  policy  thev  were  not  so  reported.  Finally. 
after  a  few  years  had  passed,  confidence  would  be  restored,  and  u 


YELLOW    FEVER.  205 

larger  proportion  of  nonimmunes  would  supply  the  material  for  a 
fresh  outbreak,  which  was  certain  to  appear  sooner  or  later.  Then 
came  a  sudden  exodus,  with  the  wrecking  of  commercial  interests, 
neglect  of  the  sick,  and  the  untold  suffering  known  only  to  those  who 
have  passed  through  a  severe  epidemic.  Here  let  me  remark  with 
emphasis  that  for  the  production  of  an  outbreak  of  yellow  fever 
three  factors  are  necessary:  (1)  Preexisting  cases  of  the  disease, 
(2)  mosquitoes  of  the  genus  Stegomyia,  and  (3)  nonimmunes  or  per- 
sons who  are  susceptible  to  the  disease.  I  would  impress  upon  you 
the  fact  that  the  absence  of  any  one  of  these  factors  will  render  it 
absolutely  impossible  for  an  outbreak  to  occur.  An  epidemic  of 
yellow  fever  is  impossible  in  the  absence  of  preexisting  cases,  for  the 
disease  can  not  be  generated  by  any  amount  of  filth,  heat,  moisture, 
or  decomposition  without  the  intervention  of  the  three  factors 
named.  Excluding  experimental  inoculation,  the  occurrence  of 
cases  of  yellow  fever  is  not  possible  under  any  conditions  without  the 
presence  of  the  proper  mosquito  to  transmit  the  infection  from  the 
sick  to  the  well.  And,  finally,  given  any  possible  local  conditions, 
any  number  of  cases  of  yellow  fever  and  any  number  of  infected 
mosquitoes,  in  the  absence  of  susceptible  persons,  cases  of  the  disease 
must  disappear. 

But  I  am  going  faster  than  I  ought.  Here  in  Galveston  you 
are  in  the  epidemic  zone  of  the  disease;  you  have  had  your  epi- 
demics, and  you  have  reason  to  guard  against  them  in  the  future. 
Your  city  was  described  30  years  ago  as  being  built  upon  an  island 
composed  of  shingle,  and  this  shingle  so  saturated  with  water  that 
the  latter  could  be  found  at  a  depth  of  a  few  inches.  The  mean 
temperature  is  about  74°,  and  the  rainfalls  are  usually  heavy  in 
April,  May,  and  June.  Owing  to  the  saturation  of  the  deeper  layers 
of  the  soil,  the  rain  water  lay  upon  the  surface  in  pools  until  it  disap- 
peared by  evaporation  in  the  dryer  months  of  the  late  summer  and 
autumn.  The  surface  pools  of  fresh  water  were  ideal  breeding  places 
for  mosquitoes,  as  also  were  the  receptacles  for  rain  water,  which  the 
early  inhabitants  collected  and  used  after  the  custom  at  New  Orleans. 
Yellow  fever  paid  its  first  notable  visit  here  in  1839,  only  a  few  years 
after  the  establishment  of  the  first  settlement.  The  population  was 
about  1,000,  and  the  people  were  located  mostly  along  the  Strand, 
in  close  proximity  to  the  wharves  and  vessels.  The  first  case  reported 
occurred  late  in  September  on  a  steamer  recently  arrived  from  New 
Orleans.  At  about  the  same  time  another  case  occurred  on  a  vessel 
anchored  only  a  few  yards  from  her.  Both  cases  were  fatal.  As 
others  were  reported  on  land  at  the  same  time,  it  is  more  than  likelv 
that  these  were  not  the  first  cases,  but  as  they  were  the  first  in  which 
black  vomit  appeared  they  were  probably  the  first  in  which  a  diag- 
nosis of  yellow  fever  could  no  longer  be  withheld.  In  this  epidemic, 
which  lasted  less  than  two  months,  we  are  told  that  there  were  250 
deaths,  which  means  the  occurrence  of  at  least  twice  as  many  cases 
among  the  population  of  1,000  persons.  It  is  further  stated  that  the 
epidemic  died  out  because  "  every  unacclimated  person  had  either 
fled  from  the  town  or  suffered  an  attack.  This  was  proved  by  the 
fact  that  when  the  refugees  began  to  return  the  disease  broke  out 
again  among  the  newly  arrived,  and  there  were  a  number  of  deaths." 
How  beautifully  this  all  fits  in  with  the  mosquito  theory,  now  that 
we  know  that  the  bite  of  the  mosquito  can  convey  the  disease  as  long 


206  U>W   FEVER. 

as  two  months  after  it  has  bitten  a  v  el  low  fever  patient.  I  have 
good  reason  to  be  a  firm  believer  in  the  theory  of  the  transmission  of 
the  disease  by  the  mosauito,  for  I  have  seen  i<>  cases  of  experimental 
yellow  fever 'produced  bv  the  application  of  infected  insects,  and  it 
was  my  good  fortune  to  be  the  first  case  amonir  them.  AmoiiLT  other 
experiments  it  was  my  privilege  to  apply  two  mox,|uitoes  of  the 
proper  genus  (Steiromyia)  to  a  patient  Buffering  with  yellow  fc\  er. 
and  57  days  later  1  applied  the  same  mosijuitor  <>lun- 

teer,  who  had  been  kept  in  strict  «piarantine  for  7S  days.  In  four  days 
he  \\as  taken  ill  with  a  typic  attack  of  yellow  fever,  from  which  he 
made  a  good  recovery. 

Returning  to  the  subject  of  Galveston.  a  few  cases  are  said   t«» 
have  appeared    in    IS-pJ.    but    in    1MI    a    violent    outbreak    raged    for 
about  six  weeks,  and  then  erased  suddenly  from  the  absence  of 
ceptible  persons.     Here  it  was  again  noticed,   however,  that    mm 
immunes  who  visited  the  town  but  once  for  the  purpose  of  shopping. 
etc.,  occasionally  returned  home  to  be  taken  ill  with  yellow  fe\ 
few  days  later.     This  continued  until  the  appearance  of  a  white  frost. 
which  we  know  benumbs  the  mosquito  and  forces  it  to  go  into  hiber- 
nation.    This,  therefore,  affords  a  rational  explanation  of  tin4  e 
of  the  first  sharp  frost,  which  has  so  long  been   welcomed   as   the 
savior  of  districts  afflicted  with  yellow  fever.     During  the  epidemic 
just  mentioned  nearly  400  deaths  occurred  in  a  population  of  about 
4,000. 

Three  years  later,  in  1847,  an  epidemic  was  declared  to  be  present 
in  the  month  of  October  and  there  were  about  200  deaths  in  a  popu- 
lation of  4,800.  In  1853,  after  an  immunity  of  six  years,  the  aeaths 
from  yellow  fever  were  535;  in  1854,  404;  in  1858,  873;  and  in  1859, 
183  in  a  population  of  about  10,000. 

In  September,  1864,  the  disease  was  again  epidemic,  the  deaths 
being  259  and  the  population  5,500.  Three  years  of  exemption  fol- 
lowed, and  in  1867  a  severe  epidemic  is  estimated  to  have  produced 
8,000  cases  and  1,150  deaths  in  Galveston  in  a  population  of  15,000. 
From  Galveston  it  was  carried  to  a  number  of  smaller  towns,  among 
which  Alleytown  on  the  Colorado  River  was  afflicted  with  200  deal  hs 
and  about  800  cases  in  a  population  of  1,500. 

During  the  same  season  Indianola  is  said  t<>  have  received  the 
infection  from  Vera  Cruz,  and  we  are  told  that  ''in  less  than  a  \\eek 
the  whole  business  part  of  the  town  was  struck  down  as  by  li<rhtninir. 
there  being  no  less  than  125  to  150  cases  taken  durinir  that  time  out 
of  a  population  of  less  than  1,000."  The  extension  of  the  disease 
was  checked  by  a  rapid  depopulation  of  the  town.  The  number 
of  deaths  amonir  the  citizens  was  about  75.  From  Indianola  the 
disease  is  said  to  have  been  carried  to  various  points  throughout 
the  State  and  even  beyond.  In  1870  and  1873  a  few  cases  occurred. 
but  the  disease  did  not  assume  epidemic  form.  There  is  reason  to 
believe, also, from  the  report  of  Dr.  1 1.  A.  West  .of  thi-  city  (Galveston  », 
that  there  were  a  few  mild  case-  in  1x97.  I  can  find  no  record  of 
any  outbreak  in  Galveston  since  that  time,  although  two  cases  ^<  re 
introduced  on  December  31  last,  but  as  you  well  know  there  were 
in  the  State  of  Texas  in  1903  over  1,200  cases  of  yellow  fever,  with 
nearly  140  deaths.  Over  1,000  cases  and  107  deaths  are  recorded 
for  I.  lone,  and  if  it  were  not  for  the  cner^'tic  mca-ures  insti- 

tuted against   the   fnosquito    there   would    undoubtedly  have  been 


YELLOW    FEVER.  207 

another  fearful  epidemic  to  record  for  the  United  States  similar 
to  that  of  1878,  during  which,  according  to  the  Board  of  Experts 
appointed  by  Congress,  more  than  100,000  persons  were  stricken 
in  their  homes,  and  20,000  lives  were  sacrificed  in  a  single  season. 
In  Memphis  alone,  according  to  Keating,  there  were  in  1878,  17,600 
cases  of  yellow  fever,  with  5,150  deaths,  a  mortality  rate  of  about 
1  in  4  of  the  reduced  population.  Scenes  were  enacted  there  similar 
to  those  described  by  Rush  in  his  account  of  the  epidemic  at  Phila- 
delphia almost  a  century  before,  when  the  streets  became  deserted, 
bodies  remained  unburied,  friends  no  longer  shook  hands  upon 
meeting,  husbands  deserted  their  wives,  wives  their  husbands,  and 
parents  their  children.  So,  in  Memphis,  we  are  told  of  a  prominent 
man  who  fled  the  city  and  refused  to  return  when  his  wife  and  chil- 
dren were  stricken  and  who  still  remained  50  iniles  away  when  notified 
of  their  death.  These  deplorable  incidents,  however,  were  more 
than  offset  by  numberless  instances  of  heroic  devotion  on  the  part 
of  Sisters  of  Charity,  nurses,  and  physicians  who  died  at  their  posts 
of  duty.  As  one  illustration  I  might  cite  from  the  little  book  on 
yellow  fever  published  in  1898  by  Dr.  W.  L.  Coleman,  of  Houston. 
Dr.  Coleman  was  present  during  the  Memphis  epidemic  and  took 
down  the  names  of  45  volunteer  physicians  immediately  after  their 
arrival.  Most  of  them  came  from  the  Northwest,  and  one  did  not 
remain.  The  others  all  contracted  yellow  fever  and  30  of  them  were 
dead  within  a  month. 

At  that  time  no  one  could  say  how  the  disease  was  contracted; 
some  held  that  it  was  of  local  origin  and  contagious,  others  that  it 
was  not  contagious;  many  believed  it  was  imported,  that  it  was 
infectious  but  not  contagious,  and  was  carried  in  some  mysterious 
way  by  the  atmosphere.  We  are  told  by  Keating  that  "Dr.  Dowell, 
of  Galveston,  says  that  in  19  cases  put  of  20  it  will  be  found  to  have 
been  introduced  or  imported/'  which  was  wonderfully  near  to  the 
truth  as  we  know  it  to-day. 

It  may  surprise  you  to  learn  that  yellow  fever  experimental 
inoculations  began  in  the  United  States  in  Philadelphia,  during  the 
yellow-fever  epidemics  in  the  years  1802  and  1803.  It  is  a  fact  that 
in  those  years  Stubbins  Firth,  a  medical  student  of  the  University 
of  Pennsylvania,  deliberately  experimented  upon  himself  by  placing 
Fresh  black  vomit  and  blood  serum  obtained  from  yellow-fever 
patients  into  wounds  made  in  his  arms  and  legs.  Failing  in  this, 
tie  inhaled  the  fumes  from  black  vomit,  which  he  heated  over  a  sand 
bath  in  a  small  room,  and  then,  making  the  residue  into  pills,  he 
swallowed  them.  He  administered  black  vomit  to  animals,  injected 
it  into  their  circulation,  and  deposited  it  in  their  tissues.  As  the 
results  of  these  and  other  experiments  were  negative,  he  concluded 
that  yellow  fever  was  neither  infectious  nor  contagious,  and  reported 
his  work  and  conclusions  in  a  graduation  thesis  in  1804. 

But  little  more  was  done  or  could  be  clone  until  the  advent  of  the 
tiew  science  of  bateriology  encouraged  the  belief  that  this  mvsterious 
malady  might  be  caused  by  a  bacterium.  The  first  to  claim  the 
iiscoverv  of  the  specific  cause  of  yellow  fever  was  Dr.  Domingo  Freire, 
of  Brazil,  who  went  further  than  this,  and  claimed  also  that  he  had 
conferred  protection  against  the  disease  by  inoculations  with  specially 
treated  cultures.  He  was  followed  by  Dr.  Carmone  y  Valle,  of  Mexico ; 
Dr.  Babes,  of  Brazil;  Dr.  Gibier,  of  Paris;  and  Dr.  Finlay,  of  Habana, 


208 

of  whom  believed  that  he  had  foiuul  the  cause  of  yellow  fever 
in  a  different  organism.  It  remained  for  Dr.  Sternheri:  to  show  that 
these  investigators  were  all  mistaken,  and  that  the  hacu-ria  found 
by  them  were  not  in  any  way  related  to  the  disease.  Dr.  Stemherj:. 
himself,  subsequently  exhausted  the  iiM  so  far  as  the  search  for 
bacteria  was  concerned;  he  also  made  e\tremel\  careful  and  thor- 
ough examinations  of  the  Mood  and  tissues  obtained  from  patients 
with  yellow  fever.  He  announced  finally  that  his  search  had  proved 
unsuccessful,  and  his  \\ork  stands  as  the  best  that  has  ever  been  done 
in  the  studv  of  the  bacteriology  of  the  disease. 

In  1897  tne sensational  announcement  was  made  that  D  -ppe 

Sanarolli,  an  Italian  bacteriologist,  working  upon  the  island  of  Fl< 
in  Montevideo,  had  di-c.  he  cause  of  yellow  fever  in  a  bacillus 

that  he  had  found  in  about  ">()  ner  cent  of  the  patients  examined  bv 
him.  He  reported  also  that  the  injection  of  pure  cultures  of  this 
bacillus  into  the  circulation  of  dogs  brought  about  an  infection 
similar  to  yellow  fever  in  the  human  beinir.  \\ith  the  vomiting  and 
other  symptoms  of  that  disease,  and  a  similar  condition  of  the  or 
after  deatn.  This  announcement  naturally  interested  Dr.  Stern; 
who  at  this  tune  had  become  Surgeon  General  of  the  Army,  and  he 
immediately  turned  to  an  organism  that  he  had  obtained  from  about 
50  per  cent  of  the  patients  examined  by  him.  that  he  had  found  to  be 
exceedingly  virulent  for  the  small  laboratory  animals,  and  which  he 
had  called  Bacillus  X,  because  he  had  been  unable  positively  t<>  iden- 
tify it.  He  obtained  a  culture  that  had  been  preserved  by  one  of  his 
former  assistants,  and  directed  Dr.  Reed  and  myself  to  undertake 
certain  experiments  with  it.  As  Dr.  Sternberg  had  never  injected  it 
into  dogs,  one  of  the  first  steps  in  our  work  was  a  duplication  of  some 
of  Dr.  SanareUi's  experiments,  viz,  to  inject  it  into  the  circulation 
of  dogs.  We  obtained  the  same  effects  as  Sanarelli  had  recorded  for 
his  yellow-fever  bacillus,  and  this  seemed  to  indicate  that  the  organ- 
isms must  be  identical.  Dr.  Sternberg  then  procured  a  cult  in 
Sanarelli's  bacillus  from  Prof .  Roux,  of  raris.  and  handed  it  to  us  for 
comparative  study.  It  is  amusing  now  to  think  of  the  fearful  respect 
with  which  we  handled  the  culture  from  Dr.  Sanarelli's  la! 
because  we  were  fully  prepared  to  accept  it  as  the  cause  of  yellow  < 
from  what  we  knew  of  Dr.  Sanarelli's  reputation  as  a  bacteriolo 
After  several  months  it  became  apparent  that  this  supposed  yellow- 
fever  bacillus  of  Sanarelli  was  nothing  more  nor  less  than  the  c«  >mm<  >n 
hog-cholera  bacillus,  an  organism  that  was  much  better  known  in 
America  than  abroad.  Sanarelli  was  evidently  at  that  time  not 
familiar  with  the  bacillus  of  hog  cholera,  for  he  pronounced  the  irerm 
obtained  by  him  "the  strangest  «>f  all  microbes  that  are  known."  A 
bitter  controversy  arose  upon  the  publication  of  our  reports  of  the  \\ork 
hi  which  we  had  found  that  Dr.  Sanarelli's  bacillus  wnen  fed  to  young 
hogs  would  produce  the  symptoms  and  lesions  of  hog  cholera,  [ndeeo, 
Sanarelli  still  contends  in  his  own  country  that  he  found  the  bacillus 
of  yellow  fever,  aeon  tent  ion  that  finds  no  support  to-day  amoiiLr  repu- 
table bacteriologists  in  this  country  or  in  Europe. 

It  is  a  remarkable  fact  that  upon  his  own  demonstrations  alon-  .  Dr. 
Sanarelli  was  awarded  large  pecuniary  prizes  and  honors  as  tin-  dis- 
coverer of  the  causative  agent  of  yellow  fever.  Unfortunately. 
Archinard  and  Woodson,  and  a  commission  from  the  Marine-Hospital 
Service,  working  in  the  United  States,  reported  that  their  results  con- 


YELLOW   FEVER.  209 

firmed  the  claims  of  Dr.  Sanarelli.  In  1897  and  1898,  the  latter  com- 
mission, consisting  of  Drs.  Wasdin  and  Geddings,  continued  their 
investigations  in  Habana,  and  in  1899  an  elaborate  report  was  issued, 
in  which  it  was  claimed  that  dogs,  rabbits,  mice,  and  other  animals 
could  be  given  yellow  fever  by  infecting  them  with  Sanarelli's  bacil- 
lus, that  infection  took  place  through  the  lungs,  and  that  a  diagnosis 
of  yellow  fever  could  be  made  by  isolating  the  bacillus  from  the  blood 
of  the  patient.  This  made  matters  rather  interesting  for  us,  but  did 
not  shake  our  confidence  in  our  results.  Bacillus  X  (Sternberg)  was 
found  to  belong  to  the  group  of  colon  bacilli. 

Finally,  in  1900,  during  the  American  occupation  of  Cuba,  yellow 
fever  became  epidemic  in  Habana.  To  take  advantage  of  the  oppor- 
tunity thus  offered,  Gen.  Sternberg  designated  a  board  to  meet  at 
Habana,  for  the  purpose  of  continuing  the  study  of  that  disease.  The 
members  of  that  board  were  Drs.  Walter  Reed,  James  Carroll,  Aris- 
tides  Agramonte  (a  Cuban  immune),  and  Jesse  W.  Lazear.  Drs. 
Lazear  and  Agramonte  were  already  at  Habana,  and  we  joined  them 
there  in  June.  Our  first  aim  was  to  confirm  or  disprove  the  claim  for 
Sanarelli's  bacillus,  which  he  had  called  B.  icteroides,  and  after  a  most 
painstaking  and  careful  investigation  of  the  blood  obtained  during 
life  from  18  undoubted  cases  of  yellow  fever,  and  of  the  blood  and 
tissues  of  11  fatal  cases  after  death,  we  were  compelled  to  report  that 
we  had  failed  to  find  Bacillus  icteroides  in  a  single  instance. 

Having  thus  disposed  of  B.  icteroides,  two  lines  of  work  now  pre- 
sented, one  an  investigation  of  the  mosquito  theory,  so  long  advo- 
cated by  Dr.  Carlos  Finlay,  of  Habana,  the  other  a  study  of  the  micro- 
organisms present  in  the  intestinal  canal  of  yellow  fever  patients.  The 
former  was  chosen,  because  of  the  numerous  points  of  resemblance 
between  yellow  fever  and  malaria,  which  was  known  to  be  conveyed 
by  the  mosquito.  Both  diseases  are  airborne;  both  are  contracted 
mostly  at  night;  both  jump  from  house  to  house  in  a  mysterious  way;, 
both  are  noncontagious ;  both  prevail  in  the  season  when  mosquitoes 
are  numerous,  and  infections  cease  to  occur  upon  the  appearance  of 
a  sharp  frost;  the  interval  of  time  elapsing  between  the  occurrence 
of  the  first  case  and  secondary  ones  in  primarily  infected  dwellings 
suggested  the  necessity  for  an  intermediate  host  in  the  conveyance  of 
yellow  fever;  it  was  noted  that  in  a  large  military  command  at  Colum- 
bia Barracks,  near  Habana,  the  only  persons  who  contracted  yellow  fever 
were  those  who  left  the  camp  after  sundown,  and  these,  after  recov- 
ery, although  they  mingled  freely  with  their  comrades,  never  infected 
them.  This  latter  observation  seemed  to  show  that  the  cause  of  the 
disease  was  not  present  on  the  body,  in  the  clothing,  or  the-  dejecta. 
A  consideration  of  all  these  points  led  us  to  decide  that  the  next  step 
should  be  to  test  the  mosquito  theory.  In  the  early  consideration 
of  this  line  of  work  the  members  of  the  board  paid  a  visit  to  Dr.  Finlay, 
who  received  them  most  courteously,  showed  them  the  common  house 
mosquito  that  he  believed  to  be  responsible  for  the  disease,  narrated 
the  work  that  he  had  done,  and  kindly  supplied  them  with  some  dried 
mosquito  eggs  for  the  purpose  of  hatching  them  out  for  study.  The 
moral  responsibility  was  next  considered,  and  in  a  later  conference  it 
was  agreed  that  the  members  of  the  board  would  themselves  be  bitten, 
and  subject  themselves  to  the  same  risk  that  necessity  compelled 
them  to  impose  on  others. 

79965°— S.  Doc.  822,  61-3 14 


210  YELLOW   FEVER. 

Dr.  Lazear  was  given  charge  of  the  mosquito  \\ork.  because  ho 
already  had  had  experience  with  other  mosquitoes.  I  was  to  con- 
tinue my  work  with  t ho  cultures,  and  Dr.  Reed  returned  to  the  Tinted 
States.  Dr.  Lazear  made  a  number  of  unsuccessful  attempts  with 
mosquitoes,  applied  one  or  several  davs  after  l>itinur  a  patient  as  Dr. 
Finlay  had  done,  and  he  himself  was  bitten  by  a  mosquito  that  he 
had  applied  to  a  mild  case  of  yellow  fever  K)  days  before.  1  reminded 
Dr.  Lazear  that  I  was  ready,  and  he  at  last  applied  to  my  arm  an 
insect  that  had  bit  ton  a  patient  with  a  severe  attack  12  'days  pre- 
viously. Four  days  later  I  had  fever,  and  on  the  day  follo\\inir  1  was 
carried  to  the  isolation  camp  as  a  patient  with  yellow  fever.  On  the 
day  that  my  fever  appeared,  Dr.  Lazear  applied  the  same  mosquito, 
with  throe  others,  to  a  soldier.  X.  V..  who  \\as  taken  sick  on  the  fifth 
day  following,  and  passed  through  a  comparatively  mild  attack. 
Scarcely  more  than  a  week  later,  Dr.  Lazear  was  applying  mos<|ur 
as  usual,  late  in  the  afternoon,  to  patients  in  the  yellow  fever  hospital. 
known  as  Las  Animas.  and  while  thus  engaged  a  mosquito  alighted 
upon  his  hand.  He  allowed  it  to  take  its  fill,  and  concluded  it  was 
one  of  the  common  culex  mosquitoes  which  were  on-sent  in  the  ho>- 
pital  in  large  numbers.  So  little  importance  did  he  attach  to  the 
incident  that  he  made  no  note  of  it,  and  related  the  circumstaii' 
me  when  he  was  first  taken  sick,  five  days  afterward.  A  week  from 
that  date  he  died,  having  been  delirious  and  affec {pfl  with  hlnr.fc  yomit 
for  several  davs.  Thus  ended  the  first  set  of  experiments,  with  The 
death  of  our  esteemed  and  unfortunate  colleague. 

Two  months  later  a  new  series  of  experiments  was  instituted  for 
the  purpose  of  confirming  the  results  already  obtained,  to  see.  also, 
whether  the  disease  could  be  contracted  from  exposure  to  soiled  or 
contaminated  articles  of  bedding,  clothing,  etc.,  and  to  dot  ermine 
whether  or  not  the  infectious  agent  was  present  in  the  blood. 

For  the  first-mentioned  experiments  an  isolation  camp,  called 
after  our  deceased  comrade  Camp  Lazear,"  was  established  in  a 
secluded  spot  about  a  mile  from  Columbia  Barracks  and  apart  from 
any  habitation.  In  this  camp  there  were  placed  three  immunes  and 
nine  nonimmunes,  including  one  immune  and  one  nonLmmuno  phy- 
sician. A  strict  Quarantine  was  maintained  and  only  the  immunes 
were  permitted  to  leave  the  camp.  If  a  nonimmuno  left,  he  was  not 
permitted  to  return.  As  newly  arrived  nonimmune  Spanish  immi- 
grants could  be  obtained  from  the  immigrant  station  at  llabana  they 
were  brought  out  and  added  to  the  command  in  quarantine.  The 
camp  consisted  of  seven  large  hospital  tents,  separated  by  a  wide 
interval  and  pitched  in  the  arc  of  a  circle.  The  nonimmuncs  dis- 
tributed through  the  tents  were  required  to  sleep  beneath  mosquito 
bars,  and  the  rule  was  rigidly  enforced.  The  plan  was  to  pick  out 
men  here  and  there  in  the  Tine  of  tents,  bring  them  down  with  infected 
mosquitoes,  and  in  that  way  establish  the  fact  that  cases  could  he 
produced  at  will  by  the  application  of  infected  mosquitoes.  It  was 
further  desired  to  show  that  an  infected  house  was  simply  one  that 
contained  active  infected  mosquitoes,  and  that  nothing  more  vrafl 
necessary  for  the  production  of  an  epidemic  in  a  susceptible  commu- 
nity. A  new,  tigntly  ceiled  frame  building  was  constructed,  20  feet 
by  14  feet,  provided  with  two  small  windows,  tightly  closed  with 
fine-mesh  wire  screens;  also  with  two  vestibules  protected  \>\ 
outer  door,  and  an  outer  and  an  inner  tightly  fitting  screen  door,  so  as 


YELLOW    FEVER.  211 

to  guard  against  the  ingress  of  mosquitoes  from  without  or  their  egress 
from  within.  Upon  entering  the  vestibule  the  screen  door  through 
which  one  passed  was  closed,  and  the  other  was  not  opened  until  it 
was  made  certain  that  no  mosquitoes  were  passing  in  or  out.  The 
lumber  used  in  the  building  was  tongued  and  grooved ;  the  walls  were 
battened  on  the  outside  and  lined  with  white  cotton  cloth  within. 
The  walls  and  floor  were  double,  and  all  crevices  were  stopped;  the 
ceiling  was  covered  with  cloth  and  made  so  low  that  mosquitoes  resting 
upon  it  could  be  captured  with  ease.  Across  the  middle  of  this  room 
there  was  built  a  wire-screen  partition  extending  from  floor  to  ceiling 
and  dividing  it  into  two  compartments,  each  with  a  separate  entrance. 
Beds  were  placed  in  each  of  these  rooms,  and  one  of  them  was 
occupied  by  two  nonimmunes  for  18  consecutive  nights.  The  bed- 
ding and  other  articles  admitted  to  the  room  were  all  disinfected. 
On  December  21,  1900,  the  date  of  the  first  occupation,  15  contam- 
inated mosquitoes  were  turned  loose  in  the  unoccupied  compartment, 
and  then  a  nonimmune  entered  and  lay  upon  one  of  the  beds,  with  his 
chest  and  limbs  exposed  for  30  minutes.  During  this  time  he  was 
bitten  by  several  insects  and  others  bit  him  again  later  in  the  day, 
when  he  lay  there  for  20  minutes.  This  procedure  was  repeated 
again  on  the  following  day,  the  last  of  exposure.  On  December  25, 
four  days  after  his  first  exposure,  this  man  who  had  remained  in 
strict  quarantine,  was  taken  ill  with  a  severe  attack  of  yellow  fever, 
from  which  he  recovered.  The  other  two  men,  who  slept  in  the 
same  room  but  in  another  compartment,  separated  from  the  mos- 
quitoes only  by  the  screen  partition,  remained  in  their  usual  health. 
Another  building  had  been  constructed  similar  to  the  above,  but 
provided  with  only  a  single  vestibuled  entrance.  It  was  equally 
protected  against  the  entrance  of  mosquitoes  and  had  two  small 
screen-protected  windows  provided  with  shutters,  so  as  to  exclude 
sunlight  as  well  as  mosquitoes.  It  contained  a  coal-oil  stove,  by 
means  of  which  the  temperature  was  kept  above  90°  during  the  day, 
and  the  atmosphere  was  provided  with  moisture.  Into  this  room, 
which  was  warm,  dark,  and  moist,  like  the  hold  of  a  ship  in  the  Tropics, 
several  boxes  containing  sheets,  blankets,  pillow  slips,  and  garments 
direct  from  the  yellow-fever  hospital  were  placed.  These  had  been 
soiled  intentionally  with  black  vomit  and  other  repulsive  material 
from  cases  of  yellow  fever.  This  room  was  then  entered  each  evening 
at  sundown  by  two  nonimmune  Americans,  one  of  them  a  physician, 
who  unpacked  the  boxes,  handled  and  shook  the  articles,  then  hung 
them  up  on  nails  in  the  walls,  and  retired  for  the  night.  Upon  rising 
in  the  morning  they  removed  the  articles  from  the  walls,  handled 
them  freely,  and  repacked  them  in  the  boxes,  where  they  remained 
until  evening.  This  procedure  of  unpacking  and  repacking,  handling, 
and  sleeping  in  the  presence  of  the  soiled  materials  was  kept  up  for 
20  consecutive  nights,  and  in  the  meantime  fresh  supplies  were  added 
as  fast  as  they  could  be  obtained.  On  one  or  two  occasions  the 
stench  drove  the  occupants  out,  but  they  returned  again  and  slept 
there.  They  spent  the  daytime  in  a  tent  nearby,  but  were  strictly 
quarantined.  The  pulse  rate  and  temperature  of  all  nonimmunes  in 
the  camp  were  recorded  three  times  daily,  and  showed  that  the  health 
of  these  men  was  not  affected  in  the  slightest  degree;  on  the  contrary, 
they  gained  in  weight. 


212  -l-OW   FEVER. 

These  v.  reeded  \\  .nines  after  tho  addition 

of  more  soiled  garments,*  etc.,  and  they  in  turn  were  followed  by 
another  two  for  the  same  period.  Some  of  these  men  slept  between 
the  sheets  and  in  the  garments  used  and  soiled  bv  yellow-l< 
patients  at  the  time  of  their  death,  and  they  even  slept  with  their 
faces  upon  towels  sailed  with  blood  that  had  been  shown  by 
inoculation  to  be  capable  of  infect  ini:  \vith  yellow  fever.  In  no 

.ill  any  disturbance  of  health  follow  the- 

the  conclusion  was  therefore  arrived  at   that    vellow  fever  can  not 
be  contracted  through  exposure  to  foinites.     if  one  stops  t«>  reflect 
that   the  mosquito  i^>  not  able  to  infect  until    U  days  or  more  after 
contamination,  one  is  forced  to  the  conclusion  that  the  yello\\-fe\  cr 
parasite,  which  has  never  been  seen,  must,  in  all  probability, 
through  a  distinct  cycle  of  development  in  the  mosquito  before  the 
insect  becomes  dangerous.     As  Dr.  Howard  has  told  you, 
spending  but  slightly  shorter  interval  is  seen  with  the  mosquito  that 
transmits    malaria.     The    developmental    phases    of    the    ma  I 

Jarasitein  the  mosquito  arc  well  known  and  have  been  demonstrated, 
udging  by  analogy,  therefore,  it  seems  justifiable  to  assume  that 
the  parasite  of  yellow  fever  appears  also  to  belong  t<>  that  <rroup  of 
obligate  parasites  whose  whole  existence  is  passed  within  the  bodies 
of  two  living  hosts,  one  of  which,  man,  is  a  vertebrate,  and  the  other, 
the  mosquito,  an  invertebrate".     This  afTords  an  explanation  of 
uselessness  of  disinfection  against  yellow  fever  as  well  as  ma  I 
and  it  also  explains  the  instances  occasionally  noted  in  the  literature, 
where  a  prompt  suppression  of  the  disease  followed  the  use  of  fm 
tion  as  well  as  disinfection. 

Returning  to  the  subject  of  the  experiments  at  Camp  La/ear,  the 
susceptibility  of  the  men  exposed  to  the  fomites  or  soiled 
was  shown  by  the  fact  that  lour  of  them  were  subsequently  ini< 
by  means  of  mosquitoes  and  blood  injections.     Four  nonimmun 
all  were  infected  oy  the  subcutaneous  injeetion  of  small  quaii 
of  blood  drawn  in  the  first  and  second  days  of  the  di  Thi> 

established  another  point  of  analogy  between  yellow  fever  and  mala- 
ria, and  demonstrated  the  presence  of  the  infectious  aircnt  in  the 
blood,  notwithstanding  that  we  had  failed  to  discover  anything  upon 
careful  microscopic  examination  of  the  blood  from  many  patients, 
including  those  in  whom  the  blood,  drawn  at  the  same  time,  pro,: 
yellow  fever  in  persons  into  whom  it  was  injected. 

Nine  additional  cases  were  produced  in  Camp  La/ear  by  the  appli- 
cation of  infected  mosquitoes,  making  in  all  10  cases  of  yellow 
brought  about  at  will.     All  were  taken  sick  within  the  u-ual  p 
of  incubation,  never  more  than  six  days.     They  were  selected  here 
and  there  in  the  different   tents,   and   no  other 'cases  occurred    than 
those  purposely  inoculated.     As  soon  as  a  case  appeared  the  patient 
was  immediately  removed  to  the  yellow  fever  isolation  camp,  a  mile 
distant,  to  avoid  the  possibility  of  any  stray  mo-quit.  .  uing 

infected  from  him.  In  no  instance  was  the  mosquito  found  to  be 
capable  of  infecting  in  a  shorter  period  than  12  days  after  biting  the 
patient,  and  one  patient  was  infected  with  two  mosquitoes  kept  as 
long  as  57  days. 

This  work  was  concluded  by  the  end  of  February.    I'M)],   when 
confirmatory  ex  peri  meir  taken   up  by  Dr.  John   (iuiier.-. 

Habana.     His  first  patient  was  infected  in  February  with  a  mosquito 


YELLOW   FEVER.  213 

obtained  from  the  Army  commission,  and  his  subsequent  inoculations 
were  unsuccessful  until  August,  when  he  succeeded  in  infecting  seven 
persons  with  mosquitoes.  Of  these  cases,  three,  unfortunately, 
proved  fatal.  Among  the  latter  was  a  young  American  nurse,  Miss 
Maas,  of  Baltimore,  who  voluntarily  submitted  herself  to  the  experi- 
ment. 

In  August,  1901,  I  returned  to  Habana,  and  obtaining  some  of 
Dr.  Guiteras's  mosquitoes,  infected  two  Spanish  nonimmunes. 
Drawing  blood  from  one  of  them  and  separating  the  serum,  I  passed 
the  latter  through  a  filter,  which  was  shown  to  be  capable  of  holding 
back  the  ordinary  bacteria.  Injection  of  the  filtered  serum  into  two 
Americans  infected  them  with  yellow  fever.  In  this  way  it  was 
shown  that  bodies  smaller  than  ordinary  bacteria  were  capable  of 
producing  yellow  fever  upon  injection,  and  our  failure  to  discover 
anything  upon  microscopic  examination  of  the  blood  of  yellow  fever 
patients  was  thus  satisfactorily  explained.  It  was  further  shown,  as 
a  point  of  great  scientific  interest,  that  blood  that  was  known  to  be 
capable  of  producing  the  disease  was  found  to  be  absolutely  harmless 
after  it  had  been  heated  to  131°  F.  for  10  minutes.  At  this  time  I 
produced  six  additional  yellow  fever  cases,  all  of  whom  recovered. 

Such  were  the  results  obtained  by  the  Army  board,  and  they  can 
be  summarized  as  follows: 

1.  Bacillus  icteroides  of  Sanarelli  was  shown   to   be  practically 
identical  with  the  bacillus  of  hog  cholera,  from  which  it  differs  only 
in  the  source  from  which  it  is  obtained. 

2.  Yellow  fever  is  transmitted  by  a  mosquito  of  the  genus  Stego- 
myia,  and  all  attempts  to  bring  about  the  infection  through  contact 
with  bedding,  clothing,  and  dejecta  of  yellow  fever  patients  have 
resulted  in  failure.     Hence  it  follows  that  disinfection  against  yellow 
fever  is  valueless. 

3.  Yellow  fever  can  be  produced  experimentally,  by  the  injection 
of  blood  drawn  in  the  first  and  second  clays  of  the  disease,  but  this  has 
no  direct  bearing  upon  the  transmission  or  prevention  of  the  disease 
in  its  epidemic  form. 

4.  The  specific  germ  of  yellow  fever  is  sufficiently  minute  to  pass 
through  the  pores  of  a  bacteria-proof  filter,  and  it  is  destroyed  by  a 
temperature  of  131°  F. 

Confirmation  of  the  mosquito  inoculations  has  been  furnished  by 
Dr.  Guiteras,  in  Habana;  Drs.  Ribas  and  Lutz,  as  well  as  the  French 
commission,  in  Brazil,  and  by  a  commission  of  the  United  States 
Public  Health  and  Marine-Hospital  Service,  at  Veracruz.  It  is  espe- 
cially gratifying  that  a  French  commission  from  the  Pasteur  Institute, 
working  recently  in  Brazil,  has  confirmed  practically  all  the  results  of 
the  American  Army  commission. 

The  following,  therefore,  may  be  safely  assumed: 

1 .  Disinfection  in  the  prophylaxis  against  yellow  fever  is  effective 
only  when  it  takes  the  form  of  fumigation  and  destroys  mosquitoes. 

2.  Yellow-fever  patients  can  be  the  source  from  which  other  cases 
spring  only  when  they  have  been  bitten  by  the  proper  mosquitoes ; 
consequently,  in  the  yellow-fever  zone  all   acute  febrile  cases  not 
diagnosed  should  be  handled  as  though  they  were  yellow  fever,  and 
should  be  kept  rigidly  behind  safe  mosquito  screens  and  netting. 
So  far  as  has  been  shown  the  yellow-fever  patient  is  dangerous  when 
bitten  by  mosquitoes  during  the  first  three  or  four  days  of  the  fever 


214  YELLOW   FEVER. 

only,  but  since  relapses  may  occur,  every  precaution  should  he 
maintained  as  long  as  the  temperature  remains  elevated. 

3.  The  hospital  intended  fur  the  treatment  of  suspected  08866  of 
yellow  fever  should  be  located  upon  ground  that  is  high,  well  drained. 
a\\ay  from  creeks,   pools,  or  standing  water  of  any  kind,   free  from 
mosquitos,  and  not  surrounded  by  grass  or  shrubbery.     All  entrances 
and  exits  to  such  hospitals  should  be  provided  \\ith  doM'-mcshed 
wire  •«•!•>.  and  similai  -hotild  he  fixed  immov- 
ably over  every                   and  other  opening  communicating  \\ith  the 

nor.     Standing  water  should    not    he   pern.it ted    in    hanvls  or 
vessels  of  any  kind,  and  broken  crockery,  tin  cans,  or  other  po^ihle 
ners  of  rain  water  should  he  systematically  searched  for  within 
:ius  of  several  hundred  yards,  and  removed. 

4.  Jn    general    sanitation,    all    surface    pools   should    he    promptly 
drainecl  and  iilled  in  with  gravel,  or  covered  \\ith  petroleum.      l'< 
leuin  should  be  applied  systematically  to  standing  \\  atcr  in  all  ditches, 
pools,  rain-water  gutters,  etc..  that  can  not  he  tilled  up  or  emptied. 
The  margins  of  ponds  should  be  deepened,  to  enable  the  fish  to  reach 
mosquito  larvae. 

5.  Water  should  not  be  permitted  to  stand  uncovered  in  hoi 
and  rain  water  in  cisterns  or  barrels,  when  not  used  for  drinking 
purposes,  should  be  treated  with  petroleum;    if  the  water  is  u-ed  for 
drinking,  all  openings,  vents,  etc.,  should  be  closed  \\ith  win 

or  tightly  fitting  covers.  Periodic  examinations  should  then  he 
made  for  wigglers  Oarva?)  or  mosquitoes,  because  the  female  mosquito 
may  pass  through  a  very  minute  opening  when  seeking  \\ater  on 
which  to  deposit  her  eggs.  By  means  or  these  and  other  similar 
measures,  the  number  of  mosquitoes  may  be  greatly  reduced,  and  the 
chances  for  the  conveyance  of  the  infection,  should  it  happen  to  he 
present,  will  be  thereby  greatly  diminished. 

Stegomyia  fasciata,  the  yellow-fever  mosquito,  is  a  house-dwelling 
and  house-breeding  insect;    particular  attention  should  therefo: 
paid  to  the  smallest  as  well  as  the  larger  collections  of  standing  water 
within  and  about  habitations. 

6.  After  the  removal  of  a  patient,  his  room  and  the  adjoining  ones 
should  be  at  once  tightly  closed  by  pasting  paper  over  all  cracks  and 
openings,  and  then  fumigated  with  insect  powder,  tobacco,  or  sulphur, 
to  destroy  mosquitoes.     When  the  room  is  opened  after  a  few  hours 
these  should  be  swept  up  and  burned. 

7.  Experience  at  Habana  has  shown  that  patients  suffering  from 
yellow  fever  upon  their  arrival  at  a  port  can  be  carried  through  a 
thickly  populated  city  to  a  properly  screened  hospital,   and   there 
treated  \\ithout  the  slightest  danger  to  the  community,  so  1m. 
they  are  rigidly  protected  against  mosquitoes.     Money  spent  for  the 
purpose  of  disinfection  against   yellow  fever  is  wasted,   for  yellow 
fever  in  epidemic  form  can  only  be  contracted  through  the  bites  of 
mosquitoes  of  a  single  genus. 

8.  The  i>on  contagiousness  of  yellow  fever  was  clearly  shown  in 
ain  localities  years  ago  before  the  use  of  disinfectants,  in  plae.-- 

where   the  yellow-fever  mosquito   did    not   exist.      The    belief   in    the 
supposed  contagiousness  of  this  disease  arose  from  its  trai: 
through  the  atmosphere  by  the  mosquito  at  a  time  when  this  insect 
was  not  suspected  or  known  to  be  concerned  in  the  transmission  of 
any  disease. 


YELLOW   FEVER.  215 

9.  When  a  house  is  infected  with  yellow  fever,  it  simply  contains 
infected  mosquitoes;  in  the  absence  of  this  insect,  no  amount  of 
filth,  heat,  or  moisture  is  capable  of  generating  the  disease. 

10.  Vessels   from  infected  localities   should   be   compelled,   upon 
entering  port,  to  anchor  at  least  a  fourth  of  a  mile  from  shore;  they 
should  never  be  permitted  to  tie  up  to  a  wharf  or  dock  in  the  city, 
except  in  northern  latitudes  during  the  cold  season  of  the  year.     In 
this  way,  the  chances  for  contaminated  mosquitoes  reaching  the  city 
can  be  reduced  to  a  minimum. 

1 1 .  As  the  yellow-fever  mosquito  does  not  bite,  as  a  rule,  between 
the  hours  of  9  a.  m.  and  3  p.  m.,  it  is  practically  safe  for  nonimmunes 
to  visit  infected  localities  between  these  hours  for  the  transaction  of 
business.     Before  9  a.  m.  and  after  3  p.  m.  they  will  run  a  greater 
or  lesser  risk  of  being  infected. 

12.  It  is  now  certain  that  before  the  lapse  of  many  years,  the  dis- 
ease, yellow  fever,  will  have  become  extinct.     The  length  of  time 
necessary  for  its  complete  eradication  will  depend  upon  the  readiness 
of  our  southern  neighbors  to  accept  the  mosquito  theory  in  toto, 
and  institute  in  their  infected  seaports  vigorous  and  energetic  meas- 
ures based  upon  it. 

13.  Another  epidemic  of  yellow  fever  should  never  be  seen  in  the 
United  States.     An  example  has  been  shown  in  Cuba,  and  the  meas- 
ures necessary  to  prevent  the  extension  of  the  disease  are  so  simple, 
so  plain  and  practicable  for  persons  in  authority,  that  the  existence 
of  an  epidemic  of  yellow  fever  in  our  country  should  alone  be  regarded 
as  prim  a  facie  evidence  of  the  culpability  of  some  responsible  person. 

In  conclusion,  I  can  not  refrain  from  asking  you  to  pay  no  atten- 
tion to  the  sensational  letters,  already  referred  to,  as  recently  pub- 
lished from  a  well-known  American  physician  on  the  island  of  Cuba. 
This  gentleman  was  at  one  time  regarded  as  an  authority  upon  yellow 
fever,  of  which  he  has  seen  a  great  deal,  but  he  is  now  five  years 
behind  the  time.  His  insinuation  that  cases  of  yellow  fever  are  still 
frequent  in  Cuba,  and  that  they  are  called  typhoid  fever,  is  a  scan- 
dalous misrepresentation  of  the  actual  truth,  and  an  unjustifiable 
reflection  upon  the  intelligence  and  zeal  of  Cuban  physicians,  like 
Drs.  Finlay,  Guiteras,  Agramonte,  Albertini,  and  others,  who  realize 
fully  the  responsibility  that  rests  upon  them,  who  have  suppressed 
yellow  fever  on  the  island  for  three  years,  and  who  are  fully  compe- 
tent to  deal  with  the  situation  there,  now  and  in  the  future. 


i:  4. 

LESSONS   TO  BE  LEARNED   FROM  THE    PRESENT  OUTBREAK  OF 
YELLOW  FEVER  IN  LOUISIANA.1 

By  JAMES  CARROLL,  M.  D.,  Assistant  Surgeon,  United  States  Army,  Wa>lnn    on   D.O, 

Tho  pi-.  NDfl  t  •  he  a  suitable  occasion  to  invite  aitenti.  n  to 

several  points  in  <  •••nneetion  with  the  epidemic  occurrence  of  \<  llo\v 
.   in  the  VIM'  ics  at  the  present  as  well  as  at  ot  her't  ime-. 

In  tho  discussion  of  the  symposium  on  yello\  .t  the  meet  b 

the  American  Public'   Health  Association  in  Washington  in    :  I 

called  attention2  to  the  necessity  during  the  epidemic  season  for 
requiring  physicians,  in  cities  whore  yellow  fever  is  prevailing  or 
likely  to  prevail,  to  report  promptly  to  the  authorities  all  cases  of 
fever  of  any  kind  coming  to  their  notice.     This  is  necessary  in  order 
that  there  may  be  no  delay  in  the  institution  of  proper  mea-m 
protect  the  community  against  extension  of  the  disease  if  it  be  yellow 
fever,  for  this  extension  will  almost  surely  take  place  in  tin-  more 
southern  latitudes  if  the  patients  are  not  protected  from  mosqn  i 
at  the  outset.     If  all  cases  of  undetermined  fever  were  promptly 
reported  and  at  once  protected  from  mosquitoes3  it  would  hardly 
be  possible  for  the  disease  to  spread  if  it  were  yellow  fever;  on  the 
other  hand,  where  the  physician  waits  for  the  appearance  of  black 
vomit,  the  golden  opportunity  passes  by,  for  it  has  been  shown  that 
in  practically  all  cases  the  disease  can  not  be  communicated 
the  fourth  day  of  the  fever.     For  this  reason  the  diagnosis  should  he 
anticipated,  and  all  febrile  patients  should  be  immediately  protected 
from  mosquitoes  until  it  is  shown  by  actual  demonstration  that  they 
are  not  suffering  from  this  disease.     Epidemics  do  not  follow  e 
introduction   of  yellow  fever;  mosquitoes  becoming   infected    may 
die  before  they  bite  a  nonimmune,  or  the  patients  may  happen  : 
treated  in  a  locality  free  from  Stegomyia.     A  group  of  ca  •  11<  >w 

fever  occurring  without  black  vomit  usuaUy  receives  the  designation 
bilious  remittent  fever,  a  diagnosis  that  should  be  erased  from  our 
text  books.     Bilious  remittent  fever,  acute  in  type  and  of  short  dura- 
tion, appearing  in  the  United  States,  is  yellow  fever,  and  it  >hould 
be  so  regarded.     Bilious  remittent  fever  was  formerly  regarded  as  a 
type  of  malarial  remittent,  but  that  was  before  the  use  of  the  micro- 
scope was  found  to  be  necessary  for  a  positive  diagnosis  of  ma  I. 
infection.     We  know  now  that  malarial  fever  is  not  a  disease  of  cities, 
but  of  outlying  districts,  while  the  bilious  remittent  lever,  so  culled, 
has  been  recorded  in  the  cities,  in  epidemic  form,  and  in  such  intii 
association  with  yellow  fever  that  fey  some  the  diseases  were  deci 
identical,  and  by  others  the  latter  was  said  to  be  only  a  modification 

« Read  at  the  thirty-first  annual  meeting  of  the  American  Public  Health  Association  at  Boston,  Sept. 

•  Report'of  the  Proceedings  of  the  American  Public  Health  Association.  >  291. 

•Since  this  paper  was  read,  I  have  been  informed  by  Dr.  E.  Lloeaga.  president  <>r  it,.-  superior  Board 
of  Health  of  Mexico,  that  the  line  of  procedure  indicated  is  now  belngloUowed  in  his  t-o 

216 


YELLOW   FEVER. 

of  the  former.  Most  interesting  and  important  in  this  connection  is 
the  statement  cited  by  La  Roche,1  in  his  chapter  on  bilious  remittent 
fever,  that ' '  the  morbid  appearances  revealed  on  dissection  are  the 
same  in  remittent  as  in  yellow  fevers."  This  statement,  however, 
was  not  wholly  accepted  by  him,  for  he  calls  attention  to  the  bronzed 
appearance  of  the  Fiver  in  certain  remittents,  a  condition  that  we 
know  results  only  from  malarial  pigmentation.  Now  that  we  can  so 
easily  differentiate  malarial  remittent  and  typhoid  from  yellow  fever, 
the  diagnosis  is  much  less  difficult,  except  where  yellow  fever  occurs 
as  a  complicating  infection. 

Our  confreres  in  Havana  have  demonstrated  to  us  that  it  is  pos- 
sible to  prevent  the  epidemic  occurrence  of  yellow  fever,  while  occa- 
sionally admitting  cases  of  the  disease  into  tlie  heart  of  a  city  in  which 
the  climatic  and  other  conditions  are  known  to  be  most  favorable  for 
its  extension  in  epidemic  form,  and  in  which  there  are  more  suscep- 
tible persons  now  than  ever  before.  The  method  suggested  here  is  in 
'many  respects  similar  to,  and  is  based  on,  the  one  adopted  during  the 
American  occupation  of  Havana. 

Since  then  it  has  been  sufficiently  demonstrated,  in  1903  and  again 
in -1905,  that  under  the  lax  system  heretofore  and  now  in  vogue, 
yellow  fever  can  easily  secure  a  firm  foothold  in  certain  of  the  south- 
ern states  and  escape  recognition  until  it  has  passed  almost  com- 
pletely beyond  control.  On  both  occasions  cited,  the  outbreak  was 
suppressed  or  limited  only  by  the  intervention  of  the  General  Govern- 
ment, which,  through  the  energetic  action  of  the  United  States 
Public  Health  and  Marine-Hospital  Service,  finally  succeeded  in 
checking  two  epidemics  that  threatened,  to  become  little  less  than 
national  calamities.  Great  credit  is  due  to  those  officials  for  the 
success  that  was  attained  in  spite  of  the  extreme  delicacy  of  the 
situation  and  the  passive  opposition  encountered  from  many  quarters. 

Our  experiences  in  Cuba  have  shown  that  for  the  exclusion  and 
suppression  of  yellow  fever  absolute  hygienic  control  is  necessary 
not  only  of  the  people  at  large,  but  of  the  patients  as  well,  and  espe- 
cially of  the  practicing  physicians.  The  aim  of  modern  medicine  is 
the  prevention  of  disease  rather  than  its  cure,  and  the  safety  and 
welfare  of  the  thousands  of  persons  exposed  demand  that  the  proper 
measures  be  instituted  and  rigidly  enforced.  No  valid  argument  can 
be  brought  forward  to  show  why  the  United  States  should  not  be  kept 
as  free  from  outbreaks  of  yellow  fever  as  the  city  of  Havana,  its  former 
endemic  home,  has  been  during  the  past  four  years. 

To  attain  this  result  the  following  requirements  seem  to  be  essential : 

1.  Our  physicians,  or  at  least  those  who  are  in  control,  must  dis- 
abuse their  minds  of  the  impression .  that  black  vomit  necessarily 
occurs  in  the  majority  of  cases  of  yellow  fever. 

2.  During  the  epidemic  season,  viz,  from  about  May  1  to  October 
31,  and  in  the  epidemic  zone,  physicians  should  be  required  to  report 
to  the  health  authorities,  immediately,  all  cases  of  fever  of  any  kind 
that  come  under  their  observation,  whether  among  their  patients  or 
not,  and  failure  to  do  so  should  be  made  punishable  under  the  law. 

3.  The  board  of  health  should  be  authorized  to  appoint,  with 
proper  compensation,  a  commission  of  three  experts,  all  of  whom 
should  be  men  of  high  reputation  as  diagnosticians.     It  should  be  the 

1  Yellow  Fever,  La  Roche,  Philadelphia,  1855,  vol.  i,  p.  590. 


218  0\V    FEVER. 

duty  of  '  imnission  to  visit   without   delay  all  cases  of  fever 

reported  to  the  health  authorities,  and  the  onus  of  diagnosis  shouhl 

on  the  commission  and  not  on  the  attending  physicians.     They 
Cthecominissit.n)  should  visit  each  patient  daily  until  the  dia.ir! 
is  established  or  the  patient  sent  to  hospital,  and  they  should  tor- 

i  promptly  to  the  health  department  a  written  report  at  each 
visit.  The  commission  should  determine  whether  or  not  the  patient 
shall  be  treated  as  a  possible  case  of  yellow  id  their  decision 

should  he  final  and  obligatory  on  all  concerned. 

4.  All  patients  presenting  the  symptoms  of  yellow  fever,  ami  all 
cases    not    cli  1     but     remaining    under    suspicion,    should     he 

d   f.»r  treatment  to  a  hospital  especially   located 

:ded    with   wire   I  -<piito   nets,   and    the   whole   or  a 

portion  of  which  has  been  set  anart  for  that  purpose.  The  yellow 
r  wards  or  hospital  should  D6  under  the  direct  control  of  the 
senior  diagnosis  commission,  and  the  patients  should  be  treated  by 
physicians  appointed  Only  on  their  recommendation  and  acting  under 
their  direction. 

5.  In  exceptional  cases,   to   be  determined   by  the  commission, 
patients  under  observation  awaiting  diagnosis  could  be  treated   in 
their  homes  beneath  mosquito  netting,  and  in  rooms  properly  pro- 
tected with  wire  screens,  until  the  nature  of  the  case  had  been  finally 
settled  to  the  satisfaction  of  the  commission. 

The  commission  and  not  the  attending  physician  should  he  held 
responsible  for  the  enforcement  of  all  clinical  measures  necessary  for 
the  protection  of  the  community,  and  they  should  be  empowered  to 
emplov  such  help  as  seemed  in  their  judgment  to  be  required.  They 
should  also  be  assisted  at  times  by  subcommissions  appointed  on  their 
recommendation. 

Under  such  a  system,  conscientiously  carried  out,  the  occurrence 
of  an  epidemic  of  yellow  fever  in  any  city  would  become  an  impossi- 
bility. Objection  can  not  be  made  on  tne  ground  of  expense  if  the 
members  or  the  diagnosis  commission  are  paid  only  for  every  \  i-it 
to  a  patient;  under  such  an  arrangement  the  cost  to  the  city  would 
be  trifling  when  compared  with  the  losses  now  sustained  by  indi- 
viduals and  the  whole  community  through  the  failure  of  practicing 
physicians  to  recognize  and  report  mild  cases  of  the  disease  And 
nerein  lies  the  crucial  point.  The  diagnosis  must  be  anticipated 
and  the  proper  precautionary  measures  oe  taken  before  the  disease 
has  fully  declared  itself.  Diagnoses  of  malarial  remittent,  and  above 
all  of  bilious  remittent  fever,  must  not  be  accepted  as  conclusive 
until  the  presence  of  malarial  or  other  parasites  has  been  demonstrated 
to  the  satisfaction  of  the  members  of  the  diagnosis  commission. 
Attention  was  called  two  years  ago  l  to  the  fact  that  over  and  over 
again,  since  the  time  of  Benjamin  Rush,  yellow  fever  has  stalked 
abroad  in  our  cities,  unrecognized,  under  the  guise  of  bilious  remit  tent 
fever.  The  time  has  come  when  a  diagnosis  of  bilious  remittent 
fever  should  no  longer  be  accepted,  for  there  is  no  such  disease  | » 
We  may  have  malarial  fever  complicated  with  jaundice,  but  this 
should  not  change  the  diagnosis  of  malaria  any  more  than  an  accom- 
panying icterus  would  change  a  diagnosis  pf  typhoid  fever.  Simi- 
arly  a  complication  of  malaria  no  longer  justifies  the  diagnosis  of 

i  Journal  Association  of  Military  Surgeons,  1903,  No.  4,  vol.  xlll,  pp.  103, 199,  and  200. 


i; 


YELLOW   FEVER.  219 

typho-malarial  fever,  and  that  term  has  properly  been  discarded. 
In  numerous  instances  it  is  stated  in  the  records  of  the  older  epidemics 
of  yellow  fever  that  the  disease  was  preceded'by,  or  began  as,  a  bilious 
remittent  fever,  just  as  in  more  recent  times  physicians  have  believed 
that  typhoid  fever  began  as  malarial  fever.  The  conclusion  is 
equally  untenable  in  both  cases,  and  the  deduction  is  obvious  that 
cases  of  so-called  bilious  remittent  fever  must  be  regarded  and  treated 
as  cases  of  yellow  fever,  unless  a  satisfactory  specific  cause  for  the 
condition  can  be  demonstrated  beyond  a  doubt.  It  is  proper  to 
mention  here  that  in  every  one  of  the  22  cases  of  yellow  fever  pur- 
posely inoculated  by  the  Army  Board  in  Cuba,  a  diagnosis  of  bilious 
remittent  fever  would  have  been  justified  if  it  had  not  been  known 
that  they  were  produced  from  true  cases  of  yellow  fever,  for,  although 
some  of  them  were  severe,  black  vomit  was  absent  from  all. 

It  may  seem  unnecessarily  severe  to  require  physicians,  under  a 
penalty,  to  report  all  cases  of  fever  coming  under  their  observation, 
but  no  other  means  will  attain  the  desired  result,  and  the  enormous 
interests  at  stake  demand  that  the  methods  instituted  be  thorough 
and  that  they  be  rigidly  carried  out.  The  appointment  of  a  board  of 
diagnosis,  as  has  been  suggested,  will  relieve  the  attending  physician 
from  the  odium  that  accompanies  a  diagnosis  of  yellow  fever  in  a 
doubtful  case,  and  the  board,  fully  appreciating  the  responsibility 
that  rests  on  them,  may  be  relied  on  to  do  their  duty.  During  the  dis- 
cussion on  yellow  fever  before  the  American  Public  Health  Associa- 
tion at  its  meeting  in  Washington  two  years  ago,  already  referred  to 
in  my  remarks,  which  were  badly  misquoted,1  I  urged  the  necessity 
for  requiring  physicians,  under  a  penalty,  to  report  all  cases  of  fever, 
in  order  that  they  might  be  examined  by  a  board  of  experts  (as  was 
done  in  Cuba)  and  treated  as  cases  of,  yellow  fever  until  the  diagnosis 
was  established.  Only  last  month,  in  a  conversation  on  this  subject 
with  a  physician  from  a  large  city  in  Texas,  he  laughingly  remarked : 
"  We  never  report  our  cases  of  yellow  fever  until  we  have  about  a  dozen 
of  them." 

The  present  epidemic  in  and  about  New  Orleans  only  serves  to  em- 
phasize the  necessity  for  such  regulations  as  are  here  suggested,  and  this 
necessity  is  further  emphasized  by  the  statement  in  the  public  press 
of  September  5  that  "  Inspector  Brady  attributed  the  continued  spread 
of  the  disease  to  the  unwillingness  or  inability  of  physicians  to  diag- 
nose mild  cases  of  yellow  fever,  and  that  physicians  of  standing  and 
ability  look  for  black  vomit  before  making  a  diagnosis.' '  We  have  else- 
where 2  cited  the  occurrence  of  the  same  difficulty  at  Key  West  in  1889, 
and  we  again  assert  that  these  physicians  may  be  thoroughly  con- 
scientious and  able  men,  but  they  are  baffled  by  the  differences  between 
the  aspects  of  the  disease  as  they  actually  find  it  and  as  they  have  been 
taught  by  the  best  authorities  to  expect  to  find  it.  It  is  the  manifest 
duty  of  local  health  authorities,  therefore,  to  relieve  the  physician  of 
the  burden  of  diagnosis  and  to  leave  that  and  the  adoption  of  protec- 
tive measures  to  the  board  of  expert  diagnosticians. 

In  this  connection  I  beg  to  be  permitted  to  call  attention  to  the 
present  situation  at  Jackson  Barracks,  a  station  of  two  batteries  of 
Coast  Artillery,  in  New  Orleans.  By  the  seventh  day  of  the  present 

1  Reports  of  the  Proceedings  of  American  Public  Health  Association,  vol.  xxix,  1904,  p.  291. 
a  Journal  Association  of  Military  Surgeons,  1903,  vol.  xiii,  No.  4,  p.  201. 


220  YELLOW  FEVER. 

month  a  number  of  cases  of  yellow  fever  had  appeared  in  the  neighbor- 
hood and  seven  of  them  in  a  block  that  approached  within  LOO  reel  of 
the  officer's  quarters.  Still  t  he  garrison  has  not  been  removed  and  up 
to  the  present  time  no  Mn-le  case  has  occurred  amoiu:  them:  e\en 
should  a  case  or  two  appear  an  epidemic  is  not  feared.  The  re. 
for  this  is  simply  that  the  medical  oihcers  know  that  it  is  absolutely 
within  their  power  to  prevent  any  epidemic  extension  of  the  disease; 
they  are  constantly  on  the  alert,  ana  all  cases  of  fever  are  handled  in 
the  beginning  as  though  they  mii:ht  he  yellow  fever. 

Again,  at  Fort  Melntosh.  in  Laredo,  Tex.,  in  1903,  there  were  only 
5  CMOS  of  yellow  fever  in  a  eommand  of  111  officers  and  men.  while 
in  the  town  alongside  them  over  1  ,<»<)()  cases  and  mere  than  ion  deaths 
occurred.  It  was  found  that  the  5  men  who  became  infected  had 
violated  orders  bv  visiting  the  town  at  ni^ht  without  wearing  the 
prescribed  mosquito  head-nets,  leather  gauntlets,  and  leiru'in. 

If,  in  t  IIA  presence  of  cases  of  yellow  fever  among  and  around  them, 
garrisons  of  soldiers  can  be  protected  from  the  infection  in  anything 
epidemic  form,  it  necessarily  follows  that  the  same  measures  and 
the  same  degree  of  vigilance  will  protect  a  community,  provided  t  he 
physicians  do  their  full  duty  and  they  are  properly  assisted  l>\   the 
authorities.     The  subject  is  one  invohinir  tne  lives  and  intere>: 
thousands  of  innocent  persons,  and  the  secret  of  success  lies  in  et » 
vigilance,  with  the  determination  to  allow  no  case,  however  mild  and 
doubtful,  to  escape  the  fullest  precautions. 


DR    ARISTIDES  AGRAMONTE 


PART  IV,— REPORTS  FROM  SANITARY  OFFICERS  IN  HABANA,  CUBA, 
DEMONSTRATING  THE  PRACTICAL  VALUE  OF  THE  SCIENTIFIC 
FINDINGS  OF  MAJ,  REED  AND  HIS  ASSOCIATES  ON  THE  YELLOW- 
FEVER  COMMISSION, 


CHAPTER  I. 

SANITATION  AND  YELLOW  FEVER  IN  HABANA. 

HEADQUARTERS,  DEPARTMENT  OF  CUBA, 

OFFICE  OF  CHIEF  SURGEON, 

Havana,  February  8, 1901. 

The  ADJUTANT  GENERAL  OF  THE  DEPARTMENT. 
SIR: 


YELLOW    FEVER,     ESPECIALLY    FROM    THE    VIEWPOINT    OF    THE    SANI- 
TARIAN. 

Yellow  fever  has  played  such  a  conspicuous  and  important  part  in 
the  mortality  of  Habana  that  it  deserves  special  consideration.  This 
infectious  disease  may  claim  Habana  as  one  of  its  oldest  and  most 
favored  haunts.  It  was  here  as  early  as  1720,  if,  as  I  believe,  we  are 
justified  in  so  regarding  the  outbreak  of  that  date  described  by  the 
historian  Pezuela,  apparently  imported  from  Vera  Cruz.  It  there- 
after broke  out  in  occasional  epidemics  like  the  historic,  ones  of  1749 
and  1762,  the  latter  being  particularly  fatal  to  the  Anglo-American 
army  which  had  just  captured  the  city,  and  causing  the  conquerors 
to  relinquish  their  prize  in  1763.  From  that  day  to  this  yellow  fever 
has  been  endemic  in  Habana,  hardly  noticeable  in  some  years,  a  mere 
smouldering  fire  when  nonimmunes  were  few,  but  quickly  lighting 
up  into  a  blaze  as  soon  as  the  fuel  of  immigration  came  within  its 
reach.  The  result  has  been  a  thoroughly  infected  city,  a  source  of 
danger  not  only  to  its  own  inhabitants  and  the  rest  or  Cuba,  but  as 
well  to  all  countries  having  commercial  relations  with  it. 

During  the  decade  1890-99,  the  recorded  number  of  deaths  was 
4,831,  giving  an  annual  average  of  483,  with  a  wide  range  from  1,282 
in  1896  to  103  in  1899.  In  1900  the  number  of  deaths  was  310. 
Thus  yellow  fever  is  not  nearly  as  fatal  in  Habana  as  typhoid  fever  in 
the  United  States,  and  its  importance  would  seem  to  have  been  very 
much  exaggerated  j  did  we  not  realize  that  its  mortality  is  not  fur- 
nished by  the  whole  population,  but  only  a  small  proportion  thereof, 
that  is,  the  nonimmunes  probably  never  averaging  more  than  1 
in  10. 

Until  a  few  months  ago  the  mode  of  propagation  of  yellow  fever 
was  uncertain;  we  were  fighting  an  unknown  enemy  in  the  dark,  an 

221 


222  YELLOW  FEVEB. 

enemy  so  wily  and  elusive  that  we  never  knew  to  what  extent-  our 
clumsy  and  expensive  methods  of  warfare  were  successful.  Hut. 
very  recently,  much  liirht  has  been  thrown  upon  the  subject  as  the 
result  of  one  of  the  most  brilliant  medical  discoveries  of  the  age.  The 
announcement  long  ago  made  by  Dr.  Carlos  Finlav,  of  llabana,  that 
mosouiti  the  agent  of  transmission  in  yellow  fever  ha-  been 

verified  and  scientifically  demonstrated  by  Maj.  Walter  Keed.  Sur- 
geon, United  States  Army,  and  his  colleagues,  in  the  most  conclusive 
manner.  It  is  true  that  the  germ  itself,  in  spite  of  the  da  in 
Sanarelli  and  his  partisans,  has  not  yet  been  isolated,  but  this  i>  ,,f 
comparatively  little  moment  to  the  sanitarian,  more  concerned  with 
prevention  than  cure.  For  our  purpose,  the  mosquito  is  the  enemy , 
and  all  our  efforts  must  be  directed  against  it.  This  war  should  be 
waged  with  a  twofold  object:  the  destruction  of  the  malaria-bearing 
anopheles  and  that  of  the  yellow-fever  bearing  culex;  thus,  at  the 
same  time,  eradicating  the  two  diseases  which  have  contributed  so 
much  to  make  Habana  a  byword  of  reproach  among  civilized  nation^. 
Practically,  then,  the  problem  consists:  First,  in  Ending  the  haunts 
and  breeding  places  of  mosquitoes  and  the  best  means  of  ex  t  i  n.urn  ish  i ni: 
them;  second,  in  carefully  protectingyellow-f  ever  patients  and  all  imn- 
immunes  with  mosquito  bars,  so  that  mosquitoes  may  not  be  inf. 
by  the  former  and  carry  the  infection  to  the  latter;  third,  in  i-datini: 
patients,  and  also,  as  much  as  is  possible,  nonimmunes,  so  that  mos- 
quitoes biting  the  former  may  not  be  able  to  reach  the  latter.  The 
knowledge  that  mosquitoes  do  not  travel  far,  seldom  more  than  a  few 
hundred  feet  if  shelter  exists,  and  that  each  house  practically  bn 
its  own,  simplifies  the  question.  The  data  being  thus  plainly  stated, 
there  does  not  appear  to  be  insurmountable  obstacles  in  the  way.  and 
we  may  confidently  expect  to  see  yellow  fever  stamped  out  in  I  la  hana 
in  the  course  of  three  or  four  years  after  the  construction  of  a  good 
sewerage  system,  provided  the  same  unremitting  efforts  are  con- 
tinued under  intelligent  medical  supervision  and  with  the  unrot  ricted 
help  of  the  State. 

The  isolation  and  protection  of  patients  is  a  most  important 
measure,  but  hard  of  successful  accomplishment  on  account  of  the 
difficulty  of  discovering  and  recognizing  all  cases.  Many  patients 
among  the  poorer  classes  are  not  seen  by  physicians,  and  the  expe- 
rience of  the  last  two  or  three  years  has  led  us  to  believe,  that  many 
cases,  especially  among  young  children,  are  so  mild  that  they  i 
unrecognized  or  are  wrongly  diagnosed.  From  these  mild,  ambu- 
latory, and  consequently  unprotected  cases  the  fever  is  mostly  spread . 
It  is  only  when  the  profession  becomes  convinced  that  such  cases 
really  exist,  and  that,  as  foci  of  infection,  they  are  as  dangerous  as 
severe  cases,  that  perfect  results  will  be  obtained. 

Our  present  knowledge  concerning  the  agency  of  the  mosquito  in 
yellow  fever  explains  much  that  was  obscure  oefore  and  furnishes 
useful  indications  to  the  Military  physician.  For  instance,  the  part 
played  by  dirt  and  filth  in  the  breeding  and  propagation  of  the  i 
was  always  problematical;  now  we  know  that  they  have  nothing  to 
do  with  it,  except  inasmuch  as  they  may  attract  and  feed  mosquitoes. 
It  is  certain  that  in  Habana,  in  1900,  no  visible  correlation  could  be 
seen  between  dirt  and  yellow  fever;  the  district  which  first  became 
strongly  infected  lies  east  and  south  of  the  Paraue  Central,  and  is 
one  of  the  cleanest  and  best  constructed,  while  tne  most  insanitary 


YELLOW   FEVER.  223 

wards  became  infected  late  in  the  season  and  only  to  a  slight  extent; 
the  malodorous  district  reserved  to  houses  of  ill  fame  did  hardly  have 
a  case.  Yellow  fever  has  not  followed  the  poor  and  unclean,  or  the 
march  of  previous  infections,  but  rather  the  movement  of  nonim- 
munes;  wherever  these  located,  there  the  infection  searched  and  found 
them,  regardless  of  the  hygienic  conditions  of  their  premises,  the  most 
aristocratic  apartments  on  the  second  and  third  floors  being  as  liable 
to  its  invasion  as  any  of  the  hovels  crowded  around  a  patio. 

We  also  know  that  digging  the  ground,  either  for  purposes  of  cul- 
tivation or  construction  or,  for  instance,  the  laying  of  sewers,  is  a 
perfectly  harmless  operation  so  far  as  yellow  fever  and  malaria  are 
concerned,  provided  no  water  is  allowed  to  stagnate  in  any  of  the 
cuts  and  ditches.  The  value  of  this  knowledge  on  the  eve  of  under- 
taking our  great  work  of  sewerage  can  not  be  overestimated. 

The  positive  agency  of  the  mosquito  in  propagating  yellow  fever 
would  naturally  argue  the  noncontagiousness  of  the  disease  and  the 
inertness  of  fomites;  but  in  order  that  the  demonstration  might  be 
complete,  Maj.  Reed  and  colleagues  also  conclusively  proved  by 
direct  experiment  that  infected  linen,  bedding,  and  effects  of  all 
kinds  are  powerless  to  convey  the  disease.  This  discovery  must  bring 
about  a  revolution  in  our  methods  of  disinfection  and  quarantine  in 
yellow  fever.  Disinfection  becomes  completely  useless,  since  there 
are  no  infectious  germs  to  destroy.  In  a  house  where  a  case  of  yellow 
fever  has  been  under  treatment  the  problem  is  how  to  reach  the 
mosquitoes  which  have  become  infected  by  biting  the  patient  and 
are  still  lurking  in  the  vicinity.  It  is  probable  that  a  certain  propor- 
tion of  mosquitoes,  after  feeding,  fly  out  in  search  of  water  wherein 
to  lay  their  eggs,  in  the  immediate  neighborhood,  but  enough  remain 
in  the  patient's  and  contiguous  rooms  to  require  action.  The  best 
way  to  destroy  them,  so  far  as  now  known,  is  by  fumigation.  Sul- 
phur fumes  are  most  efficacious,  but  otherwise  so  objectionable  that 
preference  should  be  given  to  formaldehyde,  which,  as  we  know,  is 
much  safer  and  more  convenient.  It  kills  mosquitoes  in  from  10  to 
15  minutes,  so  that  rooms  treated  with  it  need  not  be  closed  more 
than  three  or  four  hours.  The  good  effects  of  such  fumigation  seem 
to  have  been  proved  in  preventing  the  recurrence  of  a  second  case  in 
694  out  of  885  infected  houses  in  Habana,  and  by  the  absence  of  a 
single  case  in  Santiago  de  Cuba  in  1900,  after  the  epidemic  of  1899. 

The  duties  of  quarantine  officers  have  also  become  singularly  sim- 
plified. Since  we  may  assume  in  practice  that  the  infectious  germs  do 
not  exist  outside  of  man  and  the  mosquito,  the  disinfection  of  trunks 
and  baggage  on  account  of  yellow  fever  is  no  longer  justifiable;  all 
that  is  required  will  be  the  examination  of  nonimmunes  within  the 
five  days  immediately  following  their  last  exposure  to  infection,  the 
danger  of  transmission  being  from  their  own  persons  and  in  no  wise 
from  their  clothing  or  baggage.  Ships,  like  houses,  are  liable  to  har- 
bor infected  mosquitoes  and  will  continue  to  require  fumigation. 

From  what  precedes  it  must  be  evident  that  the  two  chief  factors 
in  the  propagation  of  yellow  fever  are  mosquitoes  and  nonimmunes. 
Nonimmunes  are  almost  entirely  furnished  by  immigration.  Were  it 
possible  to  completely  stop  it,  especially  from  Spain  and  the  Canary 
Islands,  for  two  or  three  years,  it  is  almost  certain  that  during  that 
short  period  all  germ-bearing  mosquitoes  could  be  destroyed,  and 
the  city  thereafter  kept  as  free  from  infection  as  Kingston  in  Jamaica 


224  VER. 

and  San  Juan  in  Porto  Rico.  Immigration,  however,  is  too  valuable 
to  the  interests  of  the  island  to  be  stopped,  or  even  cheeked,  for  the 
sake  of  stamping  out  yellow  fever,  a  disease  without  terror  and  of 
little  consequence  to  Cubans.  It  is  only  possible,  then,  to  take  such 
measures  as  will  protect  as  many  aonimmunes  as  possible  without 
fering  in  any  way  with  business  interests.  The  plan  lately 
adopted  i>  practical  and  eilicient  :  All  noninimune  immigrants  who 
do  not  come  in  answer  to  a  call  from  1  lavana  are  taken  to  a  detention 
station  on  the  healthiest  site  around  the  bay,  where  they  await  in 
comfort  and  safety  offers  of  employment.  All  employers  of  lab.. 
as  many  as  it  is  possible  to  reach,  have  been  notified  of  the  e 
of  this  station  and  invited  to  engage  there  all  the  hand-  they  need. 
Earnest  efforts  are  made  to  send  as  many  as  possible  of  these  immi- 
grants to  the  rural  districts  where  most  wanted.  In  this  way  all  are 
benefited:  the  immigrant  who  procures  work  without  hardship  or 
danger,  the  city  of  Havana,  which  is  rid  of  dangerous  nonimmune 
airdomerations,  and  employers  who  are  enabled  to  get  as  many  hands 
a<  they  may  require  with  the  least  trouble  and  expense. 

The  relation  which  Spanish  immigration  has  borne  to  yellow  i 
is  important  and  interesting.     It  has  been  most  active  in  pcrio 
peace  and  prosperity,  becoming  small  or  stopping  altogether  in 
of  political  disturbance  and  insurrection,  and  statistics  show  that  the 
spread  of  yellow  fever  among  civilians  is  directly  proportional  to  the 
number  01  immigrants. 

Soldiers,  on  the  contrary,  were  few  in  years  of  peace  and  contrib- 
uted little  to  the  yellow  fever  mortality,  but  in  troublous  times  they 
were  greatly  and  rapidly  increased,  beginning  to  arrive  as  the  civil 
immigration  began  to  stop,  so  that  their  mortality  curve  rose  as  that 
of  the  civil  population  fell.  Thus,  when  the  last  insurrection  b 
put,  in,  1895,  immigration  stopped;  on  the  contrary,  troops  \x> 
into  Havana,  and  the  result  was  a  very  high  military  mortality  in 
1896, 1897,  and  1898.  When  the  American  troops  took  possession  of 
Havana  on  January  1,  1899,  the  whole  population  was  practically 
immune,  and,  the  Spanish  troops  having  departed,  cases  of  yellow 
fever  ceased.  The  American  troops  formed  the  only  susceptible  or 
nonimmune  element  and  disciplinary  measures  were  successful,  with 
one  slight  exception,  in  preventing  their  contagion.  It  the:. 
happened,  naturally  enough,  that  only  few  scattered  cases  were 
observed  during  the  spring  and  summer  of  1899.  As  soon  as  peace 
was  assured  the  current  of  immigration  was  resumed,  and  in  greater 
volume  than  ever.  The  result  was  immediately  seen  in  the  number  of 
cases,  which  steadily  increased  from  August  to  December,  the  number 
for  December  being  larger  than  for  the  same  month  in  any  previous 
year;  this  is  more  striking  because  the  death  rate  of  yellow  fever 
generally  rises  to  its  maximum  in  August  and  September  and  shows 
a  marked  decline  from  October  to  December. 

During  the  years  1899  and  1900,  40,384  immigrants  arrived  at 
Habana,  namely  16,260  in  1899  and  24,124  in  1900,  a  prcai  majority 
of  them  nonimmunes  and  at  least  50  per  cent  remaining  in  the  city 
of  Habana.  They  still  continue  to  come  at  about  the  same  r 
With  these  figures  of  the  largest  i  1 1 1  migration  on  record  in  the  same 
space  of  time,  what  happened  was  to  Be  expected  and  unavoidable, 
namely,  an  usually  large  number  of  cases  of  yellow  fever  in  the 
summer  and  fall  of  1900  and  corresponding  high^mortality,  although 


YELLOW   FEVER.  225 

the  deaths  (310)  did  not  reach  the  annual  average  of  the  past  decade. 
The  effect  of  cold  weather  on  the  infection  was,  as  usual,  well  marked  • 
from  74  in  October  the  number  of  deaths  decreased  to  57  in  Novem- 
ber, 20  in  December,  and  only  7  in  January,  1901. 

The  subject  of  immunity  against  yellow  fever  is  very  interesting 
and  deserves  a  few  remarks.  Immunity  is  not  enjoyed  by  all 
Cubans,  as  popularly  believed,  but  only  by  those  residing  in  cities, 
not  by  those  who  have  lived  from  infancy  in  the  interior  rural  dis- 
tricts. In  other  words,  immunity  is  only  enjoyed  by  the  residents 
of  centers  where  yellow  fever  is  endemic;  it  is  not  enough  to  have 
lived  in  a  tropical  climate;  one  must  have  lived  in  an  infected  locality. 
The  inference  therefore  is  strong  that  immunity  is  acquired  only  by 
an  attack  of  the  disease;  there  is  no  other  infectious  disease  against 
which  immunity  is  obtained  in  any  other  way,  and  there  is  no  reason 
to  believe  that  yellow  fever  is  an  exception  to  the  rule.  Under  the 
former  belief  that  it  was  acquired  by  the  absorption  of  germs  through 
the  respiratory  passages,  it  was  possible  to  conceive  the  possibility 
of  a  very  slow  but  constant  infinitesimal  absorption  which  might  in 
time  produce  immunity  without  any  apparent  lever,  but  such  a  con- 
ception is  no  longer  tenable  if  the  germs  are  introduced  directly  into 
the  blood  by  the  mosquito.  Those  physicians  who  assume  a  priori 
that  Cubans,  whether  they  live  in  the  city  or  country,  can  not  have 
yellow  fever,  decline  to  recognize  it  when  they  find  it  in  natives ;  they 
call  it  "fiebre  de  borras"  and  consider  it  a  special  form  of  malaria, 
which,  strangely  enough,  only  occurs  in  this  island. 

Since  the  great  majority  of  Cubans  are  immune  and  immunity  is 
only  acquired  by  an  attack  of  the  disease,  we  are  compelled  to  the 
conclusion  that  nearly  all  natives  of  Cuba  must  have  yellow  fever 
in  their  youth — probably  in  the  first  few  years  of  their  lives.  At 
that  age  the  disease  appears  to  be  mild  and  comparatively  harmless, 
and  we  may  fairly  assume  that  the  5,000  children  annually  born  in 
Habana  have  it  in  such  form  that  it  is  generally  unrecognized  by 
physicians  who  diagnose  it  under  the  comprehensive  headings  of 
malaria,  calentura  or  meningitis.  In  this  connection  it  is  interesting 
to  observe  that  in  epidemic  years  the  proportion  of  deaths  among 
children,  not  diagnosed  yellow  fever,  is  noticeably  greater. 

Here  an  interesting  question  suggests  itself.  If  Cubans  have  yellow 
fever  in  infancy  in  such  a  mild  form  as  not  to  endanger  life  and  remain 
immune  thereafter,  why  should  they  endeavor  to  eradicate  the  dis- 
ease in  the  island,  so  that  their  descendants  will  lose  immunity  and 
become  liable  to  any  epidemic  that  may  break  out  hereafter?  The 
answer  is  that  foreign  visitors  and  immigrants  have  natural  rights 
that  Cubans  are  bound  to  respect;  that  epidemics  can  be  guarded 
against  and  avoided ;  and  lastly,  that  although  Cuban  infants  have 
the  disease  in  an  apparently  mild  form,  it  will  probably  be  found, 
when  the  matter  is  investigated  and  the  obscure  diagnoses  of  many 
of  the  reported  cases  of  death  carefully  analyzed,  that  a  larger  pro- 
portion of  deaths  among  children  than  is  generally  believed  is  due 
to  yellow  fever  or  complications  therefrom. 

A  few  words  in  closing  upon  the  result  of  treatment  of  yellow-fever 
cases  at  Las  Animas  hospital,  an  establishment  intended  for  the 
reception  and  treatment  of  all  contagious  diseases,  but  chiefly  yellow 
fever.  During  the  year  1900  it  was  under  the  direction  of  Maj. 
W.  C.  Gorgas,  chief  sanitary  officer,  who  devoted  to  it  much  of  his 
79965°— S.  Doc.  822,  61-3 15 


226  YKI.l.OW    l  l  VI  i;. 

valuable  time.  The  hospital  is  pleasantly  situated  in  the  outskirts 
of  the  city  and  as  completely  equipped  with  material  and  personnel 
&8  any  hospital  of  its  kind  in  the  I'niled  States.  Ameriean  trained 
nurses  being  in  attendance.  An  ainlndance.  carrying  physician 
and  nurse,  is  :d\\ays  in  readiness  to  go  when  summoned,  and  the 
v  is  taken  to  save  patients  all  unnecessary  fatigue  or 
exertion  in  transit. 

The  patients  sent  to  this  ho-piial  may  he  divided  in  l  \\  o  rla- 
Kirst.  Americans  (including  few  nther  foreigners),  the  majority  of 
them  brought  there  at  their  o\\  n  request  early  in  the  disease,  hut 
includiiiLT  al>o  not  a  few  homeless  vagabonds  and  drunkards ;  second, 
Spaniards,  mostly  of  the  lowest  classes,  too  poor  and  thriftless  to 
belong  to  any  of  the  <|iiintas  <le  salud. 

It  can  easily  be  seen  therefore  that  Las  Animas  receives  m«'>t  of 
the  worst  cases,  generally  after  the  disease  has  lasted  several  days. 
not  infrequently  the  patients  being  unconscious  and  occasionally 
moribund,  as  shown  by  the  fact  that  out  of  ."is  deaths.  Is  occurred 
within  three  <lays  after  admission.  During  the  year.  L'7'J  < 
of  yellow  fever  were  admitted:  1(>7  Americans.  71  Spaniards,  and 
::i  of  other  nationalities:  J  M  recovered  and  ."is  died.  gi\  inir  a 
general  death  rate  of  'JL.'W.  Taking  the  three  leading  and  bc-l 
conducted  private  hospitals  in  llabana  for  comparison,  namely. 
the  Dependientes,  (\>\  adonga.  and  Beneiica,  we  lind  that  during  the 
year  their  yellow  fevi  r  death  rates  were  24.35,  -7..M.  and  24.35 
respectively,  each  higher  than  that  of  Las  Animas,  although  their 
patients,  being  members  of  the  centros  or  clubs  to  which  the  hospi- 
tals belong,  are  generally  admitted  early  in  the  course  of  the  di 
and  therefore  in  much  more  favorable  condition-  for  succe— ful 
treatment. 

At  Las  Animas  the  death  rate  of  Spaniards  was  36.48  and  that  of 
Americans  12.57,  a  most  remarkable  difference  when  we  bear  in 
mind  that  all  patients  there  receive  the  same  identical  treatment 
in  the  same  wards.  This  difference  is  partly  due  to  the  fact  that 
Americans  are  in  better  physical  condition,  with  greater  power  of 
resistance,  but  chiefly  to  the  circumstance  that  they  are  admitted 
early  and  have  the  full  benefit  of  the  treatment.  In  this  respect 
the  status  of  Americans  at  Las  Animas  may  be  fairly  compared  to 
that  of  the  Spaniards  received  at  the  above-mentioned  hospitals. 
and  yet  their  mortality  is  only  one-half  that  of  the  latter.  Such 
results  furnish  food  for  reflection.  At  Las  Animas  patients  are 
treated  almost  entirely  on  the  expectant  plan;  medicines  are  avoided 
until  there  is  a  clear  indication  for  their  use:  absolute  re>i.  very 
careful  dieting,  and  the  constant  attention,  day  and  night,  of  trained 
nurses  have  been  the  main  features  of  treatment.  The  key  to 
success  in  the  treatment  of  yellow  fever,  I  believe,  is  good  nuixiii" 
at  the  hands  of  specially  trained  women.  Such  nur>ing  is  e\pen>i\e. 
and  in  Cuba  has  been  practicable,  so  .far,  only  in  few  other  ho-pitaU. 
but  any  method  of  treatment  which  saves  lives  H  always  found  to  be 
the  cheapest. 

V.  1 1  \  v  vi:i». 
Major  and  Surgeon,  Unltnl  Shifr*  Arm;/.  <  '/<  iff  Surgeon. 


CHAPTER  2. 
REPORT  OP  THE  HABANA  YELLOW  FEVER  COMMISSION. 

HABANA,  January  3, 1902. 

SIR:  In  compliance  with  your  request  that  I  should  make  a  report 
of  my  department,  as  chairman  of  the  Yellow  Fever  Commission,  for 
the  six  months  ending  December  31,  I  have  the  honor  to  inclose  the 
said  report. 

Very  respectfully,  CHARLES  FINLAY, 

Chairman  of  the  Yellow  Fever  Commission. 
Maj.W.C.GoRGAs, 

Surgeon,  United  States  Army, 

Chief  Sanitary  Officer  ofHabana. 


HALF-YEARLY  REPORT  OF  THE  HABANA  YELLOW  FEVER  COMMISSION,  JULY  TO 

DECEMBER,  1901. 

During  the  ^resent  term  (July  1  to  Dec.  31,  1901)  the  Yellow 
Fever  Commission  of  Habana  has  examined  and  investigated  118 
cases,  reported  as  follows:  94  yellow  fever  suspects  (37  of  which 
were  confirmed  as  "natural  yellow  fever"  and  10  as  "experimental 
yellow  fever");  7  suspected  glanders  (the  diagnosis  was  confirmed 
in  4) ;  4  leprosy  (confirmed  in  3) ;  6  suspected  smallpox  (none  of 
which  were  confirmed) ;  1  typhus  fever  (not  confirmed) ;  1  relapsing 
fever  (not  confirmed);  5  reported  as  "infectious  fever"  (in  2  that 
diagnosis  was  maintained,  inasmuch  as  these  cases,  while  presenting 
clinical  characters  suggestive  of  an  infection,  could  not  be  identified 
as  malaria,  typhoid,  influenza,  and  Malta  fever,  and  were  therefore  con- 
sidered as  belonging  to  the  group  of  ' '  Tropical  unclassed  fevers) . 

The  37  cases  diagnosed  as  "natural  yellow  fever"  have  been  dis- 
tributed in  Table  I,  so  as  to  differentiate  those  whose  infection  had 
originated  in  this  city  from  others  who  were  brought  to  Habana, 
already  sick  or  infected,  from  other  parts  of  this  island,  and  also 
from  those  who  came  from  foreign  ports. 

TABLE  I.— 1901. 


July. 

August. 

September. 

October. 

November. 

December. 

Totals. 

Cases. 

Died. 

Cases. 

Died. 

Cases. 

Died. 

Cases. 

Died. 

Cases. 

Died. 

Cases. 

Died. 

Cases. 

Died. 

Habana  

7 

6 
0 

3 

1 

0 

7 

3 

1 

1 

0 
0 

9 

0 
0 

2 

0 

0 

0 

1 
1 

0 

0 
0 

0 

0 
2 

0 

0 
1 

0 

0 
0 

0 

0 
0 

23 

10 

4 

6 

1 
1 

Other    towns 
(Cuba)  
Foreign  ports.. 

13 

4 

11 

1 

9 

2 

2 

0 

2 

1 

0 

0 

37 

8 

227 


•228 


FELLOW   FEVEB. 
TABLE  U.—Expfrimentalcasa. 


Pled 


October.     November 


Cans. 


ber.    I  Nove 
Died.  Cans. 


Pled 


Totals. 


Ill 


The  wonderfully  small  number  of  yellow-fever  cases  and  deaths  in 
Hahana  duriiu:  the  epidemic  ,.f  the  present  yearia  an  unprec- 

edented event,  and  since  it  can  not  be  accounted  for  by  any  climati-- 
tinns  nor  by   a   lack  of  nnnimmunes  or  of  opportunities  fur  a 
reproduction  of  the  yellow-fever  jjcrni  through    the  introduction  of 
>  from  outside,  we  are  bound  to  admit  that  it  must  be  attributed 
to  the  killing  of  contaminated   mosquitoes  when  >   \\ere  sup- 

posed to  exist,  and  to  the  protection  of  noniiumunes  in  mity 

of  infected  houses  against  the  bites  of  those  insects,  as  the  sanr 
department  has  been  doing  since  Februar}r. 

MANNER  IN  WHICH  THE  INVESTIGATION  HAS  BEEN  CONDUCT  K I  >. 

The  conclusive  demonstration  of  the  mosqui  to  theory  by  l>r.  Meed, 
a  year  airo.  and  by  Dr.  Guite'ras  this  summer — has  made  it  all  the 
more  necessary  that  the  investigation  of  \cllo\\-fe\  ci  <1  be 

carried  out  with  jrreat  care,  so  as  to  secure  a  reliable  dia- :  id  to 

discover,  if  possible,  the  source  whence  the  infection  hasLecn  derived. 

The  method  practiced  by  the  commission  has  been  as  folio v 
data  contained  in  the  original  report  are  carefully  gone  over  at  the 
bedside  of  the  patient  and  additional  particulars  inquired  into  in  order 
to  discover,  if  possible,  the  probable  source  of  his  infection.     A  clinical 
history  of  the  case  having  been  obtained  from  the  physician  in  ch. 
it  is  minutely  scrutinized,  and  the  patient  is  then  carefully  examined 
by  each  of  the  members  present.     Particular  attention  is  given  to  the 
examination  of  the  urine  for  albumen,  and  it  is  believed  that,  while 
sources  of  error  are  avoided,  so  small  a  quantity  as  10  centigrams  of 
pure  albumen  per  liter  would  not  escape  detection,  ;  >.:ni/.able 

trace,  by  the  methods  employed.     The  different  organs  are  ex  pi 
to  detect  or  exclude  any  lesion  to  which  some  of  the  symptoms  might 
be  attributed,  and  every  circumstance  in  antecedents  ol  the  patient 
is  duly  taken  into  account. 

As  a  rule,  the  secretary  of  the  commission,  before  the  meeting  of  t  he- 
board,  has  collected  blood,  sputa,  pus,  or  other  available  material. 
according  to  the  nature  of  the  disease  reported,  and  the  said  material 
has  been  examined  for  malarial  parasite  or  bacteria,  tried  with  the 
\Yidal  test,  etc.  In  the  case  of  private  patients,  supplementary  infor- 
mation has  been  obtained  by  the  secretary  from  the  atiei,. 
physician,  and,  if  necessary,  the  latter  is  requested  to  be  p 
meeting  of  the  board.  Whenever  any  doubt  remains  in  the  minds 
of  the  members  the  decision  is  deferred  and  the  patient  rcc\:- mined 
as  often  as  may  be  necessary.  In  fatal  cases,  provided  the  family  or 
friends  of  the  patient  do  not  obj.  autopsy  is  made,  notes  of  the 

findings  recorded,  and   hystolugieal  specimens  preserved   or  cultures 
prepared  for  subsequent  examination.     The  physician  in  < 
always  expected  to  notify  the  commission  or  to  report  the  case  again 


YELLOW   FEVER.  229 

if  the  subsequent  course  of  the  attack  should  throw  some  doubt  upon 
the  decision  of  the  board,  in  which  event  a  reversal  of  the  first  diag- 
nosis would  be  voted  if  the  majority  of  the  members  decided  that 
there  was  occasion  to  do  so. 

USEFULNESS   OF    EXPERIMENTAL   CASES   FOR   DIAGNOSIS. 

In  the  diagnosis  of  mild  cases  of  yellow  fever  it  has  been  of  great 
advantage  to  the  commission  to  have  the  support  of  Dr.  Reed's 
observation  in  one  of  his  experimental  cases,  showing  that  an  un- 
doubted attack  of  the  disease  may  run  its  full  course  without  present- 
ing any  trace  of  albumen  in  the  urine.  Similar  cases  had  been 
observed  in  private  practice  by  members  of  the  commission,  and  some 
of  them  have  come  before  the  board.  The  same  may  be  said  with 
reference  to  the  importance  of  the  typical  fever  curve  as  an  element 
of  diagnosis  in  nonalbuminuric  cases. 

SOME  KNOWLEDGE  OF  THE  LIFE  CYCLE  AND  HABITS  OF  THE  STEGOMYIA 
NECESSARY   IN    ORDER    TO    FOLLOW   TRACK    OF   AN    EPIDEMIC. 

The  importance  of  ascertaining  the  source  of  the  infection  in  every 
confirmee!  case  of  yellow  fever  is  self-evident,  since  the  sanitary 
department  is  thereby  enabled  to  take  prompt  measures  calculated 
to  control  the  propagation  of  the  disease.  But  that  investigation, 
according  to  the  now  accepted  etiology,  can  not  be  successfully 
accomplished  without  a  knowledge  of  certain  details  concerning  the 
life  of  the  yellow-fever  mosquito  which  are  not  easily  found  in  the 
current  literature  on  that  subject,  and  it  may  not  be  considered  out 
of  place  to  recapitulate  them  in  this  report. 

The  species  of  gnat  which  transmits  yellow  fever  (Stegomyia 
txniata,  Theob.-Culex  mosquito,  R.  D.)  is  diurnal  and  crepuscular, 
for  it  may  be  met  with  at  any  hour  between  daybreak  and  nightfall, 
and  takes  its  rest  during  the  night.  The  males  never  bite  nor  suck 
blood;  the  females  only  do  so  after  they  have  mated,  and  never  lay 
their  ova  before  having  sucked  blood.  After  a  complete  feed  of 
blood  the  insect  will  not  bite  again  until  all  the  contents  of  its  stomach 
have  been  digested  or  discharged ;  this  process  requires  from  48  to  60 
hours  in  summer,  but  may  be  delayed  2  or  3  days  more  in  cool 
weather.  The  wings  of  the  Stegomyia  are  so  small  that  after  a  full 
meal  it  must  be  unable  to  fly  to  any  height  or  even  to  any  consider- 
able distance  on  a  level.  It  shuns  the  sunshine,  avoids  flying  across 
open  waters,  and  keeps  away  from  the  wind.  Its  eggs  are  laid  in  a 
peculiar  manner,  some  entirely  out  of  the  water,  so  that  they  are  apt 
to  remain  unhatched  during  several  weeks  or  months,  and  yet  may 
develop  a  brood  after  that  lapse  of  time  when  they  happen  to  be  cov- 
ered with  water  of  a  suitable  temperature.  It  is  probably  by  this 
means  that  the  species  is  propagated  during  the  cooler  months  of  the 
Cuban  climate.  The  Stegomyia  breeds  in  any  collection  of  water 
(a  very  small  quantity  is  needed)  in  the  yards,  gardens,  basements  of 
nouses,  often  in  the  lye  water  used  by  washerwomen  in  this  country; 
but  also  inside  of  rooms  when  water  has  been  allowed  to  stand  sev- 
eral days  in  basins,  jugs,  or  open  bottles.  A  new  brood  may  develop 
in  9  or  10  days  if  the  larvae  are  abundantly  provided  with  food  (bread 
crumbs  seem  to  agree  very  well  with  them),  otherwise  several  weeks 
may  elapse  .before  the  winged  insect  emerges  from  its  pupa  case. 


230 

When  the  temperature  falls  to  20°  C.  the  insert  is  disim -lined  to 
fly,  and  below  15°  or  10°  (\  it  is  benumbed  and  unable  cither  to  fly 
or  to  bite.  It  is  killed  by  temperatures  below  five/iiiir  point  or 
fcbove  45°  C.;  probably  :in  U)32  C,  i-  it-  optimum  temperature. 

The  Steiromyia  ia  very  domestic  in  its  habits  and  will  not  be  likely 
to  leave  the  premi-es  oii  which  it  has  taken  up  its  quarter-  BO  long  as 
it  finds  in  it  the  necessary  conditions  for  the  completion  of  its  life 
cycle  (opportunities  for  satisfy i m:  it-  craving  for  human  blood,  water 
in  which  it  may  lay  its  ova,  and  an  agreeable  atmosphere  Miitcd  t<>  it- 
tastes  ami  of  the  reouired  tempera! n»v)  In  the  ah-ence  of  any  of 
[risitefl  it  will  migrate  into  the  nearc-t  place  where  they  may 
be  sati-tied. 

The  Stegomyia  becomes  con tamin at e(l  and  acquires  the  faculty  of 
t  ran-mit  tinur    the  disease   only   after   having    bitten   a  yell. 
l»at lent  within  the  first  5  or  6  days  of  his  attack.     During  the  li 
or  3  days  of  its  contamination  its  bite  may  sometime-,  i  an 

attenuated  form  of  the  disea-e.  but  after  that  period  the  insect  loses 
for  a  while  the  faculty  of  inoculating  the  disease  in  any  form,  ami  it 
is  only  when  12  or  more  days  have  passed  since  its  contamination 
that  it  acquires  the  power  of  producing  a  well-marked  attack  of  yel- 
low fever,  the  virulence  of  its  oite  being  then  considerably  greater  in 
summer  than  in  winter.     The  contaminated  Stegomyia  retains  t ' 
after,  during  its  lifetime  (which  may  last  70  aays),  the  facult 
reproducing  the  disease  every  tune  that  it  chances  to  bite  a  non- 
immune. 

The  manner  in  which  a  nonimmune  may  become  infected  is  appar- 
ently under  the  following  circumstances: 

(1)  By  visiting  a  place  where  contaminated  mosquitoes  exist,  at  a 
time  when  those  insects  happen  to  be  in  a  condition  to  bite  and  pic- 
pared  to  inoculate  the  disease. 

(2)  By  the  fact  that  a  case  of  yellow  fever  has  occurred  in  the 
neighborhood  and  mosquitoes  contaminated  from  that  patient  have, 
for  some  reason,  been  induced  to  migrate  into  the  non immune 's 
dwelling. 

(3)  By  the  conveyance  of  contaminated  mosquitoes  in   parcels, 
boxes,  etc.,  or,  possibly  caught  under  a  hat  while  biting  the  nead  of 
a  visitor  on  his  way  to  the  nonimmune's  house. 

(4)  During  the  hot  summer  days  the  Stegomyia  is  apt  to  fly  out 
into  the  street,  under  porches,  etc.,  suggesting  the  possibility  of  their 
biting  a  yellow  fever  patient  on  his  way  to  the  hospital  if  the  carriage 
or  the  unprotected  ambulance  happens  to  be  detained.      In  Mich  a 
case,  the  insect,  thus  contaminated,  would  afterwards  take  refuge 
in  one  of  the  houses  on  the  road  to  the  hospital,  and  the  imnimmnnes 
in  that  house  might,  in  due  time,  be  inoculated  by  the  infected 
mosquito. 

A    PRACTICAL   ILLUSTRATION    OF   THE    MOSQUITO   THEOIM 

As  an  illustration  of  the  ways  in  which  the  yellow  fever  may  be 
acquired,  according  to  the  preceding  statements,  and  <>f  the  dillicul- 
ties  with  which  the  sanitary  department  has  had  to  contend  this 
year  in  preventing  the  disease  from  spreading  over  the  whole  city. 
the  following  instance  may  be  given  as  one  in  which  the  yellow  fever 
commission  was  deeply  interested. 


YELLOW    FEVER.  231 

In  one  of  our  best  hospitals  in  this  city  (Quinta  de  Dependientes) 
the  upper  story  of  a  new  building  is  reserved  for  yellow  fever  patients 
and  suspects.  That  floor  being  divided  into  a  right  wing  for  con- 
firmed cases  and  the  left  wing  for  cases  under  observation,  the  landing 
of  the  stairs  occupies  the  space  between  the  two  large  screened  doors, 
facing  each  other  and  opening  into  each  of  the  two  departments! 
Though  well  provided  with  wire  netting,  two  defects  were  subse- 
quently noticed  in  the  disposition  of  these  wards:  the  height  of  the 
ceilings,  which  prevents  mosquitoes  from-  being  seen  when  they 
occupy  the  upper  part  of  the  rooms,  and  the  absence  of  any  syphon 
or  trap  in  the  pipe  leading  off  the  water  from  a  basin  under  the 
hydrant.  Under  these  conditions,  mosquito  larvae  might  be  bred 
outside  the  building  where  the  defective  pipe  opens  and  the  winged 
insect  might  find  its  way  into  the  yellow  fever  ward,  remaining  there 
unseen  after  having  bitten  some  of  the  patients.  In  fact,  larvse 
were  observed  by  us,  on  one  occasion,  in  the  water  jug  used  in  that 
ward. 

On  the  14th  of  August  of  this  year,  two  nonimmunes  were  admitted 
into  the  observation  ward  with  a  fever  which  appeared  suspicious 
but  only  turned  out  to  have  been  a  mild  attack  of  influenza.  Both 
were  discharged  on  the  18th.  One  of  them  lived  at  Florida  Street, 
No.  2*4,  the  other  in  a  bakery  in  Aguila  Street,  No.  185,  opposite 
the  Tacon  market.  The  man  from  Florida  Street  was  attacked,  on 
the  20th  (two  days  after  leaving  the  hospital)  with  fever  and  devel- 
oped a  mild  yellow  fever.  His  "house  was  duly  fumigated  and  all 
the  contaminated  mosquitoes  must  have  been  killed,  for  no  other 
case  occurred  in  that  neighborhood.  The  other  man  (No.  1),  who 
lived  at  the  bakery,  was  also  attacked  with  yellow  fever,  but  not 
until  the  24th  (six  days  after  leaving  the  hospital),  and  two  other 
men  (Nos.  2  and  3),  who  worked  in  the  same  bakery  and  slept  in 
rooms  near  his  own,  were  also  attacked,  on  the  same  day  and  the 
next  respectively  (Aug.  24  and  25).  We  must  therefore  infer  that 
No.  1  had  brought  with  him  from  the  hospital  some  of  the  contami- 
nated mosquitoes  which  had  inoculated  him,  and  the  incubation  was 
shorter  in  the  two  other  men  than  in  his  own  case.  The  bakery  was, 
of  course,  fumigated  and  most  of  the  contaminated  mosquitoes 
probably  killed;  but  the  disposition  of  the  house  and  of  its  neighbor- 
hood was  particularly  unfavorable,  and  some  of  the  numerous  insects 
which  had  had  &  chance  of  biting  one  or  other  of  the  three  simul- 
taneous cases  must  have  escaped  and  flown  across  the  narrow  street 
into  the  porch  of  Tacon  market,  where  fruit  and  flower  venders  lay 
out  their  goods  on  the  floor  under  the  porch  and  sit  or  stand  the 
greater  part  of  the  morning  waiting  for  purchasers.  Two  of  those 
flower  venders  (Nos.  4  and  5)  were  attacked  with  yellow  fever  on  the 
7th  and  llth  of  September,  respectively;  the  last  of  these  developing 
into  a  fatal  case,  the  first  of  the  series.  These  two  men  lived  in  the 
Cerro,  where  they  had  their  garden  near  Tulipan  Park. 

Their  dwelling  was  fumigated  effectively,  for  no  other  case  of  yellow 
fever  occurred  m  the  neighborhood.  The  owner  of  the  bakery  on 
Aguila  Street  lived  in  a  house  at  the  back  of  it,  on  Amistad  Street, 
No.  136,  and  (No.  1),  when  questioned  by  the  members  of  the  com- 
mission at  the  hospital,  had  told  them  that  after  his  attack  of  influ- 
enza he  had  first  gone  to  the  owner's  house.  That  house  was  there- 
fore probably  infected  and  duly  fumigated ;  but  from  here  also  some 


232  YELLOW 

of  the  contaminated  insects  must  have  escaped  and  taken  refuse  in 
a  oaf 6  close  by,  Amistad  Street,  No.  130,  where  the  hartendci 
was  attacked  with  yellow  fever  on  the  12th  of  September.     This 
house  was  also  fumigated,  but  the  >ame  contaminated  insects  which 
had  bitten  this  case  or  others  from  the  same  source  must  have  ciX) 
Dragones Street  and  entered  another  hou>e  in  the  next  block.  AHUM  ad 
l.»5,  where  a  man  servant  i  No.  7)  was  attacked  witli  fatal  yellow 
fever  on  the  14th  of  September.     The  next  two  cases  occurred  in  t  wo 
newly  arrived  immigrants  (No.  8  and  No.  9)  who  lived  together  in  a 
room  at  Kicla.  No.  :V2,  a  food  distance  from  the  infected  ouarter:   but 
they  informed  us  that  they  were  in  the  habit  of  going  almost  every 
evening  to  a  house  in  the  block  next  to  that  of  (No.  77  Amist  ad 
96,  but  on  the  other  side  of  the  street,  to  chat  with  an  immune  IV 
of  theirs.     These  two  men  were  attacked  on  the  21st  and  22d  of 
September.     The   killing   of   mosquitoes   at   their   dwelling   pr< 
efficacious,  for  no  other  cases  occurred  near  Kicla  32:    hut  a  lew  of 
the  contaminated  insects  still  remained  in  the  block  of  (No.  7),  for  in 
a  large  tobacco  factory  occupying  the  south  front  of  that  block  two 
of  the  workmen  (No.  10  and  No.  11)  were  attacked  on  the  Jxth  of 
September.     This  time,  however,  the  fumigation  and  killing  of  the 
mosquitoes  within  and  around  the  tobacco  factory  must  have  killed 
the  last  of  the  infected  insects,  for  no  other  case  of  yellow  fever  has 
been  reported  since  in  Habana. 

DESIDERATUM. 

The  danger  of  new  invasions  which  might  insidiously  acquire  such 
proportions  that  they  should  prove  difficult  of  control,  comes  prin- 
cipally from  the  want  of  a  sure  landmark  by  which  to  recognize  even 
the  mildest  forms  of  the  disease,  a  want  which,  it  is  feared,  must 
subsist  so  long  as  the  germ  of  the  disease  has  not  been  definitely 
identified.  With  the  certainty  that  the  said  germ  is  contained  in 
the  blood  of  the  patient  and  also  in  the  head  of  the  contaminated 
stegomyia,  it  was  thought  that  Drs.  Reed  and  Carroll  could  not 
fail  to  discover  that  germ,  knowing  that  they  had  apparently  the 
best  of  materials  to  work  upon  and  the  assistance  or  experts  well 
trained  in  the  investigation  of  animal  and  vegetable  germs.  Their 
failure  to  do  so  has  therefore  caused  general  disappointment.  The 
Yellow  Fever  Commission,  howerer,  considers  it  one  of  its  duties  not 
to  let  the  matter  drop;  and  to  avail  itself  of  Dr.  Guiteras  s  permission 
and  valuable  cooperation  for  pursuing  the  search  for  the  yellow-fever 
germ  at  the  laboratory  of  his  experimental  station  whenever  a  fa\  Ar- 
able opportunity  for  doing  so  presents  itself. 

CHARLES  FINL.U  . 
Chairman  of  the  Yellow  Fever  Commission. 

HABANA,  January  3,  1902. 


Many  years  before  the  Yellow  Fever  Commission  was  organ i/ed, 
Dr.  Carlos  J.  Finlay,  of  Habana,  had  formed  the  opinion  that  yellow 
fever  was  conveyea  by  the  bites  of  mosquitoes  and  had  fbcea  upon 
the  Stegomyia  calopus  as  the  culpable  airent.  On  June  30,  1881, 
he  began  a  series  of  experiments  to  prove  the  transmission  of  the 


YELLOW   FEVER.  233 

disease  by  this  insect,  believing  that  he  could  in  this  way  produce  a 
mild  type  of  fever  which  would  convey  immunity.  He  bred  the 
mosqvitoes  in  captivity  and  developed  a  technique  for  transporting 
them  and  placing  them  upon  the  patients,  and  between  the  date 
above  mentioned  and  the  arrival  of  the  Yellow  Fever  Commission  in 
Cuba  he  had  made  103  experiments  of  which  he  regarded  a  consid- 
erable number  as  successful. 

In  the  light  of  our  present  exact  knowledge  of  the  length  of  incu- 
bation of  yellow  fever  in  man  and  the  considerable  period  of  incuba- 
tion in  the  mosquito  between  the  time  of  biting  and  when  she  be- 
comes able  to  transmit  the  infection,  and  also  the  very  brief  period 
(three  days)  at  the  begining  of  the  disease  during  which  alone  the 
patient  is  able  to  infect  the  mosquito,  it  must  be  recognized  that 
probably  none  of  Dr.  Finlay's  experiments  were  successful,  but  none 
the  less  must  credit  be  given  for  what  Col.  Gorgas  has  termed  the 
11  scientific  clairvoyance"  with  which  he  had  conceived  his  theory 
and  the  enthusiasm  'with  which  he  maintained  it. 

When  Maj.  Reed  went  into  Habana  to  consult  him,  before  begin- 
ning the  work  of  the  board,  he  gave  him  eggs  of  Stegomyia  calopus 
which  he  specifically  stated  were  those  of  the  mosquito  which  con- 
veyed the  disease,  and  the  first  experiments  of  the  board  were  made 
with  mosquitoes  grown  from  these  eggs.  As  Dr.  Finlay  was  the 
originator  of  this  theory,  and  was  of  great  assistance  to  the  com- 
mission, the  above  report  of  his,  which  is  of  scientific  as  well  as  his- 
torical value,  is  published  in  this  place,  although  it  is  recognized  that 
some  of  the  views  expressed  by  him  are  at  variance  with  the  findings 
of  the  commission. 


(  '1!  MM  FU    3. 

REPORT  OF  MAJ.  W.  C.  GORGAS,  MEDICAL  CORPS,  UNITED 

STATES  ARMY. 

1 1 KADQUARTERS    DEPARTMENT   OF   CUBA. 

Miiicr   Of  (11111    S\\ITAKY   OFIICKK  OF   11  \BA\A, 

.Inly  12,  1902. 

(.!  \n:\i  :   I   herewith  forward  the  report  of  the  sanitary  depart- 
ment. hrinLrinu:  the  account  of   the  work  up  to  May  20  of  the  pr< 
year. 

This  hcini:  the  final  report  of  the  sanitary  department  of  the  city 
of  Hahana  under  the  military  government,  it  miirht  he  useful  to 
review,  in  a  general  way,  the  work  of  the  department  since  its  incep- 
tion in  1899. 

The  great  object  of  sanitation  for  Cuba,  and  particularly  for 
Habana,  as  far  as  the  United  States  was  concerned,  was  the  erad- 
ication of  yellow  fever.  For  over  200  years  this  disease  had,  at 
short  intervals,  devastated  the  Atlantic  and  Gulf  coasts  of  the 
United  States,  causing  great  loss  of  life,  and  still  greater  iinancial 
loss,  due  to  the  entire  cessation  of  commerce  which  occurred  during 
the  epidemic.  It  is  estimated  that  the  money  loss  caused  directly 
by  the  epidemic  of  1878,  which  affected  particularly  the  lower 
Mi-sissippi  Valley,  amounted  to  $100,000,000,  and  in  years  when 
there  was  no  epidemic  quarantines  had  to  be  kept  up  against  the 
infected  regions  around  the  Gulf  of  Mexico,  which  stopped  almost 
all  travel  and  greatly  interfered  with  commerce.  The  United 
States  had  come  to  look  upon  Habana  as  the  particular  point  from 
which  infection  was  spread.  Yellow  fever  has  been  continuously 
present  in  this  city  since  1762.  Every  month  in  every  year  during 
that  time  there  have  been  some  cases.  In  all  other  localiti. 
X<  »rth  America  where  yellow  fever  occurred,  it  occurred  epidemically ; 
that  is,  the  locality  was  free  from  the  disease  for  a  longer  or  shorter 
time.  In  places  above  the  frost  line  winter  always  puts  an  end  to 
the  disease,  and  in  localities  in  the  Tropics  it  always  terminates  after 
a  greater  or  lesser  period  of  years  from  the  exhaustion  of  the  nonim- 
mune material.  It  was  therefore  hoped  by  the  military  authorities 
that  if  yellow  fever  could  be  controlled  in  Habana  the  United  S: 
would  be  free  from  danger  of  epidemic  invasion. 

One  of  the  most  prominent  objects,  then,  that  the  military  govern- 
ment had  before  it  during  its  stay  in  Cuba  was  the  control  of  yellow 
fever,  and  for  this  purp<  -e  we  paid  great  attention  to  the  improve- 
ment of  the  hygienic  conditions  all  over  the  island.  But  Ha1 
being  the  only  endemic  focus  in  the  island,  and.  for  that  matter, 
anywhere  else  in  North  America .  the  energies  of  the  military  govern- 
ment were  concentrated  at  this  point. 

None  who  knew  anything  of  yellow  fever  had  any  dear  idea  how 
its  eradication  was  to  he  accomplished,  but  (hero  was  a  general 
hdief  and  hope  that  \>\  improving  the  sanitary  conditions  the  disease 

234 


YELLOW   FEVER.  235 

here  could  be  greatly  decreased,  and  possibly  in  the  course  of  a 
number  of  years  gradually  gotten  rid  of,  as  has  been  the  case  in  the 
cities  of  the  United  States.  But  no  one,  I  think,  who  knew  anything 
of  yellow  fever  practically  would  have  ventured  to  predict  that 
much  could  have  been  done  in  this  line  in  the  course  of  three  years. 

In  Habana  the  government  went  vigorously  to  work,  rapidly 
organizing  street  cleaning,  disposal  of  garbage,  and  the  cleaning  of 
premises.  In  a  very  few  months  the  streets  were  as  clean  as  those 
of  any  modern  city  and  the  garbage  regularly  disposed  of.  But  the 
internal  sanitation  of  houses  and  the  organization  of  the  sanitary 
department  for  the  reporting  and  control  of  contagious  and  infectious 
diseases,  and  similar  matters,  took  a  longer  time. 

In  the  early  part  of  1899,  the  first  year  of  the  military  occupation, 
very  little  yellow  fever  occurred.  The  preceding  five  years  had 
been  years  of  war,  and  for  the  last  few  months  the  American  blockade 
had  practically  put  an  end  to  immigration  into  Habana,  and  the 
nonimmune  population  was  pretty  well  exhausted,  so  that  there 
were  few  left  capable  of  having  this  disease.  In  January,  there  was 
one  death;  in  February,  none;  in  March,  one;  in  April,  two;  in 
May,  none;  in  June,  one,  and  in  July,  two.  That  is,  in  the  first 
seven  months  of  1899  there  were  only  seven  deaths  from  yellow 
fever.  The  military  governor  of  the  city,  Gen.  Ludlow,  felt  sure  that 
the  measures  which  were  being  taken  had  pretty  well  eradicated  it. 

But  about  the  1st  of  August,  Spanish  immigration  began  to  pour 
into  Habana,  and  between  August  and  December  some  12,000 
immigrants  arrived  in  the  city,  about  60  per  cent  of  whom  settled  in 
Habana.  This  at  once  started  up  yellow  fever,  and  by  December  of 
1899  we  were  having  a  severe  winter  epidemic.  This  continued 
right  along  through  1900,  during  which  year  we  had  a  very  sharp 
epidemic,  having  in  all  some  1,400  cases. 

The  general  sanitary  conditions  had  improved,  as  indicated  by 
the  falling  death  rate,  in  a  very  satisfactory  manner;  but  our  work 
was  evidently  having  no  effect  upon  yellow  fever.  This  disease  was 
under  control  everywhere  else  in  the  island,  but  the  principal  means 
of  reducing  it,  the  deportation  of  the  nonimmune  population,  so 
successful  everywhere  else,  was  not  practicable  in  Habana. 

By  the  beginning  of  1901  the  sanitary  department  was  pretty 
well  satisfied  that  ordinary  sanitary  measures  were  having  no  imme- 
diate effect  upon  yellow  fever.  The  city  during  the  year  1900  was 
as  clean  and  in  as  good  sanitary  condition  as  it  was  possible  for  labor 
to  make  it,  and  affairs  could  not  be  gotten  into  better  condition  until 
after  the  completion  of  a  sewer  system. 

In  the  summer  of  1900  a  commission  of  Army  medical  officers 
headed  by  Maj .  Walter  Reed,  United  States  Army,  had  been  sent  to 
Cuba  for  the  investigation  and  study  of  yellow  fever.  Due  to  the 
financial  assistance  given  by  the  military  governor  to  this  commis- 
sion, they  were  enabled  to  experiment  on  the  human  subject.  They 
took  up  the  theory  advanced  by  Dr.  Carlos  Finlay  of  Habana,  in 
the  year  1880,  that  the  Stegomyia  mosquito  was  the  sole  means  of 
the  transmission  of  yellow  fever.  Dr.  Finlay  had  maintained  this 
theory  for  some  20  years,  and  had  done  considerable  experimental 
work  in  this  direction. 

The  commission,  through  elaborate  and  careful  experimentation, 
proved  this  to  be  correct,  and  in  February,  1901,  Dr.  Reed  read  a 


236 

paper  before  the  International  Sanitary  Congress,  in  Habana.  giving 
the  results  of  their  work.  This  idea  was  so  new  and  so  entirely 
Contrary  to  all  former  theories  on  the  subject,  and.  apparent  1 
all  former  experience,  that  the  paper  was  received  with  scant  belief. 
I  myself  had  seen  the  work,  and  was  convinced  that  the  mosquito 
could  convey  yellow  fever,  but  I  was  hardly  prepared  to  believe  that  it 
was  the  only  wa  .  <\  the  ordinary  way,  of  conveying  the  disease. 

But  all  ordinary  sanitary  measures  for  the  preceding  two  \< 
had  been  flat  failures.  Yellow  fever  at  the  heirinning  of  !!»()]  was 
about  as  bad  as  it  had  ever  been  in  Habana  at  that  time  <>f  the  year. 
The  city  was  infected  in  every  part,  and  there  was  present  probably 
the  largest  nonimmune  population  that  had  ever  In-fore  been  in 
Habana. 

1  had  very  little  hope  of  accomplishing  much;  it  seemed  to  me  that 
even  if  the  mosquito  did  convey  yellow  fever,  he  could  not  be  gotten 
rid  of,  and,  apparently,  from  all  past  experience,  the  mosquito 
not  the  only  way,  or  even  the  principal  way,  of  conveying  the  disease; 
but,  as  he  evidently  could  convey  the  disease,  it  was  our  duty  t<> 
take  precautions  in  this  direction. 

The  military  governor  readily  granted  the  necessary  appropriation 
and  authorized  the  employment  of  as  large  a  force  as  needful  tor  m<»s- 
quito  work.  Work  was  commenced  on  this  line  February  4,  1901, 
and  pushed  hi  every  direction.  The  results  soon  began  to  be  appar- 
ent. In  January  there  were  seven  deaths  from  yellow  fever;  in  Feb- 
ruary, the  first  month  of  mosquito  work,  five  death-:  in  March,  one 
death;  none  in  April,  May,  or  June;  one  in  July;  two  in  August ;  and 
two  in  September,  and  for  the  nine  months  following  September, 

1901,  not  a  single  case  nor  a  death  has  occurred  from  this  disease. 
This  result  convinced  the  sanitary  department  that  the  mosquito  not 
only  could  convey  yellow  fever,  but  that  it  was  the  ordinary  way, 
and  the  only  way,  at  least  in  Habana,  for  the  conditions  in  Habana 
during  1901  were  as  favorable  for  a  yellow  fever  epidemic  as  they  had 
ever  been.     The  city  had  the  largest  nonimmune  population,  proba- 
bly, that  it  had  ever  contained.     Infection  was  scattered  in  every 
part  of  the  city;  not  only  so,  but  the  small  towns  surrounding  the 
city  were  thoroughly  infected,  and  were  constantly  sendi: 

into  the  city.  We  continued  the  same  sanitary  measures  that  had 
been  taken  during  the  preceding  year,  and  which  had  not  had  the 
slightest  effect  upon  the  march  of  yellow  fever;  but,  in  addition,  we 
we  took  measures  looking  to  the  Stegomyia  mosquito  as  the  means 
of  conveying  the  disease.  Immediately  after  the  adoption  of  th«->e 
measures,  yellow  fever  began  to  decrease,  and  by  September  had 
been  entirely  eradicated  from  the  city. 

The  demonstration  is  the  more  effective  in  Habana  from  the  fact 
that  in  all  other  cities  of  North  America  yellow  fever  laatfl  f<>r  a 
greater  or  lesser  number  of  years,  and  then  disappears  from  natural 
causes,  to  reappear  again  when  conditions  are  favorable.  In  Habana 
the  conditions  have  been  different.  For  150  years  yellow  fever  has 
been  constantly  present  in  the  city.  From  September,  1901,  to  July, 

1902,  not  a  single  case  nor  a  death  has  occurred.     In  the  150  } 
referred  to,  not  any  year,  probably,  can  be  picked  out  in  which  (hir- 
ing the  same  period  there  were  less  than  100  deaths. 

Tliis.it  seem-  t"  me,  is  a  practical  demonst  rat  ion,  given  in  the  only 
endemic  focus  for  yellow  fever  in  North  America,  and  in  a  year  when 


YELLOW   FEVEB.  237 

the  conditions  were  most  favorable  for  the  development  of  the  disease, 
of  the  fact  that  the  Stegomyia  mosquito  is  the  only  method  of  trans- 
mitting it — a  fact  proved  by  the  Army  commission. 

Under  Army  administration  the  death  rate  in  Habana  has  de- 
creased in  a  marked  degree.  In  1898,  the  number  of  deaths  was 
21,252,  giving  a  rate  of  91.03;  in  1899,  the  first  year  of  our  occupa- 
tion, we  had  8,153  deaths,  giving  a  rate  of  33.67;  in  1900,  we  had 
6,102  deaths,  giving  a  rate  of  24.40;  in  1901,  we  had  5,720  deaths, 
giving  a  rate  or  22.11 ;  for  the  first  four  months  of  1902  there  occurred 
1,896  deaths,  which  if  kept  up  for  the  year  would  give  5,688  deaths, 
a  rate  of  20.68  for  the  year. 

Thus  it  can  be  seen  that  under  the  military  government,  in  a  little 
over  three  years  the  death  rate  was  reduced  from  91.03  to  20.68. 
The  latter  rate  would  be  a  favorable  one  for  the  better  class  of  cities 
in  Europe  or  the  United  States.  And  this  has  come  about  without 
making  any  permanent  sanitary  installations,  such  as  sewage.  The 
city  was  kept  as  clean  as  it  was  possible  for  labor  to  make  it,  with 
regard  to  trie  streets,  disposal  or  garbage,  and  the  interior  of  the 
houses.  But  every  house  in  Habana,  somewhere  under  the  house, 
still  has  a  cesspool,  the  flow  from  which  sinks  into  the  surrounding 
ground,  and  as  this  has  been  going  on  for  400  years,  the  ground  itself 
is  as  thoroughly  saturated  with  organic  matter  as  is  possible. 

The  authorities  had  hardly  hoped  for  such  marked  improvement 
until  this  system  of  cesspools  has  been  done  away  with  by  a  good 
system  of  sewage.  But  apparently  the  condition  referred  to  has  no 
very  great  effect  upon  the  general  health  of  the  city;  the  improve- 
ment has  come  about  from  a  careful  street  cleaning,  disposal  of  garb- 
age, internal  sanitation  of  houses,  and  rigid  control  of  infectious  and 
contagious  diseases. 

Our  work  down  here  has  been  a  useful  lesson  in  municipal  sani- 
tation. The  same  thing  could  be  accomplished  by  any  community 
anywhere  else,  if  they  were  willing  to  spend  money  and  labor  upon 
it.  No  elaborate  machinery  of  any  kind  is  necessary;  merely  men 
and  brooms. 

The  primary  object  of  the  war  with  Spain  was  the  liberation  of 
Cuba  from  Spanish  domination,  but,  at  the  same  time,  the  United 
States  had  hoped  to  accomplish  a  good  deal  in  improving  the  sani- 
tary condition  of  the  island.  In  this  she  has  succeeded  beyond  her 
utmost  expectations,  and  the  results  in  Cuba  have  been  a  new  de- 
parture in  military  conquest.  The  only  other  people  who  bear 
comparison  with  us  in  attempting  to  improve  the  sanitary  condi- 
tions of  a  tropical  country  are  the  English,  and  neither  in  Jamaica  nor 
in  India  have  they  been  very  successful  in  this  respect. 

Much  to  our  surprise,  we  find  that  not  only  can  a  native  city  like 
Habana  be  made  as  healthy  as  the  better  class  of  cities  in  the  United 
States,  but  that  our  own  troops,  with  proper  care,  thrive  just  as 
well  in  the  Tropics  as  they  do  in  the  Temperate  Zone.  With  the 
troops,  the  health  conditions  have  steadily  improved,  until  at  the 
evacuation  of  Cuba  the  health  rate  was  better  among  them  than  the 
average  of  troops  in  the  United  States. 

Our  first  year  in  Cuba,  1898,  with  an  average  of  8,345  men,  we 
had  a  death  rate  from  disease  of  67.94  per  thousand.  The  health 
conditions  steadily  improved  during  the  four  years  of  our  occupation, 
and  for  the  last  three  months  of  1902,  with  an  average  strength  of 


238  YKl.LOW    FHVEK. 

'  inon,  wo  had  a  death  rate  from  disease  of  1.70  per  thousand. 
Tliis  means  that  the  firM  year  of  our  life  in  the  Tropics  \\  e  lost  07 
men  out  of  every  thousand,  from  disease;  the  last  year  of  our  slay, 
we  had  profited  by  our  experience  to  such  an  extent  that  \ve  lost 
only  7  men  per  thousand. 

From  our  experience  in  Cuba,  several  useful  lessons  can  he  de- 
dueed.  We  find  that  the  native  in  the  Tropics,  with  the  same  sani- 
tary precautions  that  are  taken  in  the  Temperate  Zones,  can  he  just 
as  healthy  and  have  just  as  small  a  death  rate  as  the  inhabitants  of 
the  Temperate  /one:  that  to  brini:  this  about ,  no  elaborate  machinery 
of  any  kind  is  needed:  that  it  can  be  attained  by  any  community, 
no  matter  how  ooor.  if  they  are  willing  to  spend  sudicient  labor  in 
cleaning,  and  observing  well-known  rules  with  regard  to  di-< 
that  the  North  American  Anglo-Saxon  can  lead  juM  as  healthy  a 
life  and  live  just  as  long  in  the  Tropics  as  in  the  Tniled  Stale-. 

But  by  far  the  most  important  sanitary  lesson  is  with  regard  to 
yellow  fever — that  this  disease  is  only  conveyed  by  the  stegomyia 
mosquito;  that  the  disease  can  readily  be  eradicated,  even  when  ii 
has  gotten  a  lirm  hold,  and  easily  kept  from  establishing  itself  by 
taking  measures  looking  to  the  mosquito  as  its  can 

1  look  forward  in  the  future  to  a  time  when  yellow  fever  will  ha\«> 
entirely  disappeared  as  a  disease  to  which  mankind  is  subject,  for  I 
believe  that  when  the  yellow  fever  parasite  lias  once  become  extinct 
it  can  no  more  return  than  the  dodo  or  any  other  species  of  animal 
that  has  disappeared  from  the  earth. 

Very  respectfully,  W.  C.  GORI;.\>. 

Major,  Medical  Corps,  United  States  Amu/. 

Brig.  Gen.  LEONARD  WOOD, 

United  States  Army,  Washington,  D.  C. 


PART  V— A  FEW  GENERAL  DIRECTIONS  WITH  REGARD  TO  DESTROY- 
ING MOSQUITOES,  PARTICULARLY  THE  YELLOW-FEVER  MOSQUITO, 


By  W.  C.  GORGAS, 

Colonel,  Medical  Corps,  United  States  Army} 


As  this  article  is  not  intended  for  the  reading  of  people  who  have 
given  any  particular  attention  to  the  facts  at  present  known  of  the 
way  in  which  the  mosquito  carries  disease  from  one  person  to  another, 
I  think  it  best  to  briefly  call  attention  to  the  leading  points  in  our 
present  knowledge  of  this  subject. 

Malaria  and  yellow  fever  are  the  two  great  diseases  with  which  the 
mosquito  is  concerned.  They  are  by  far  the  most  important  diseases 
in  the  tropical  countries  of  the  Western  Hemisphere,  and  play  a  great 
part  in  the  sickness  of  the  southern  part  of  the  United  States.  Up  to 
25  years  ago  it  was  universally  believed  that  malaria  was  caused  by  a 
gas,  or  miasm,  arising  from  the  decomposition  of  dead  vegetable  mat- 
ter in  hot  countries,  but  about  that  time  a  French  army  surgeon  in 
Algeria,  Laveran  by  name,  noticed  that  if  he  looked  sufficiently  care- 
fully with  his  microscope,  in  the  blood  of  persons  suffering  from 
malaria,  he  could  almost  always  find  a  very  small  animal  parasite. 
This  little,  living  being  got  into  the  blood  in  some  way,  Laveran  did 
not  know  how,  fed  upon  the  red  blood  corpuscles,  and  was  apparently 
the  cause  of  the  disease  which  we  call  malaria.  Laveran's  discovery 
was  a  great  advance  in  our  knowledge  of  the  disease,  and  it  was 
gradually  accepted  by  all  the  medical  world. 

A  careful  search  was  made  for  the  parasite  by  many  investigators, 
but  it  could  only  b.e  found  in  the  blood  of  human  beings  suffering  from 
malaria.  Where  else  it  was  bred  and  how  it  got  into  the  blood  of 
man  no  one  could  find  out.  About  this  time  it  was  discovered  by  an 
English  army  surgeon,  Dr.  Manson,  that  a  small  worm — the  Filaria 
sanguinis  Jiominis — was  introduced  into  the  body  by  the  bite  of  a  mos- 
quito. (This  worm  causes  the  disease  among  human  beings  known  as 
filariasis,  and  to  it  are  due  the  enormous  and  unsightly  swellings  of 
the  legs  and  other  parts  of  the  body  seen  by  our  people  in  Cuba  and 
the  Philippines,  it  is,  however,  a  disease  very  rarely  found  in  the 
United  States,  and  not  of  much  importance  to  us.  I  only  mention  it 
here  in  connection  with  my  story  of  the  mosquito.) 

About  15  years  after  the  discovery  of  Laveran  that  malaria  was 
due  to  an  insect  in  the  blood,  and  of  Manson,  that  a  certain  worm 
which  caused  disease  was  introduced  into  the  human  blood  by  the  bite 
of  a  mosquito,  another  great  English  army  surgeon,  Ronald  Ross, 

*  Washington,  Government  Printing  Office,  1904. 


240  YII.LOU 


discovered  that  the  malarial  para-it  e  was  found  in  a  certain  species  of 
mosquito  —  the  anopheles  —  after  the  insect  had  bitten  a  human  being 
suffering  from  malaria.  With  his  microscope  ho  followed  the  life 
history  of  this  parasite,  from  the  stomach  of  the  mosquito,  through 
the  vails  of  the  stomach  into  the  mosquito's  b<>d\  ,  and  finally  im 
sah'vary  glands.  In  the  saliva  of  the  mosquito,  the  little  organism 
was  found  in  large  numbers,  and  when  biting  man,  for  the  purpose  of 
getting  blood,  the  mosquito  injects  her  fatal  saliva,  just  as  does  the 
rattlesnake  when  he  bites.  This  discovery  of  Dr.  Ross  \\as  demon- 
strated in  the  most  positive  manner. 

An  Italian  living  near  Rome,  in  Italy  (malaria  is  verv  bad  in  the 
neighborhood  of  Rome),  while  sutlering  from  a  malarial  attack  was 
'i  by  an  anopheles  mosquito.  This  mosquito  was  thou  taken  to 
London,  England,  whore  they  have  no  malaria,  and  a  healthy  young 
man,  who  had  never  had  malaria,  was  bitten  by  her.  In  a  lew  days  the 
young  man  had  a  well-marked  attack  of  malaria,  with  the  u-ual  s 
tom-,  and  the  malarial  parasite  was  seen  by  the  microscope  circulat  ing 
in  the  blood  of  the  patient  and  feeding  upon  the  red  blood  corpu 
of  his  blood.  And,  again,  men  were  taken,  put  into  house-,  screened 
so  t  hat  mosquitoes  could  not  get  in,  and  spent  weeks  in  this  unhealthy 
part  of  Italy  without  getting  sick.  Yet  this  particular  part  of  Italy 
is  considered  so  unhealthy  that  during  the  summer  season  neither 
native  nor  foreigner,  who  can  avoid  it,  spends  a  night  there. 

A  night  spent  in  the  Campania  used  to  be  thought  a  certain  way  to 
contract  malaria,  the  idea  being  that  the  foul  air  from  the  ma 
caused  the  disease.  Yet  it  is  now  seen  that  entirely  unacclimated  men 
can  breathe  this  air  with  safety,  provided  onlv  that  they  live  in  screened 
houses  and  are  not  bitten  by  mosquitoes.  These  and  similar  fact  s  n  m- 
vinced  the  scientific  world  that  the  malarial  organism  gets  into  the 
blood  of  the  human  being  through  the  bite  of  the  anopheles  mosquito, 
and  in  no  other  way. 

Before  the  year  1900  it  was  universally  believed  that  yellow  f. 
was  carried  from  person  to  person  and  spread  generally  by  a  germ 
which  up  to  that  time  had  not  been  discovered.  The  germ  v 
posed  to  travel  from  person  to  person  by  contact  with  those  sick  of  the 
disease,  or  by  means  of  clothing  or  other  articles  which  had  been  near 
the  sick,  and  its  development  was  believed  to  be  greatly  favored  by  all 
conditions  which  increased  filth.  There  were  a  good  many  fact  s  in  t  he 
spread  of  the  disease  which  were  difiicult  to  account  for  under  t  his  sup- 
position, but  nevertheless  it  was  the  best  explanation  possible,  and, 
as  I  said,  was  almost  universally  accepted,  both  by  physicians  and 
people  generally. 

During  the  year  1900  the  Army  of  the  United  States  had  entire 
control  of  Ilabana,  at  that  time  the  great  center  of  yellow  lexer  for 
the  world.    An  excellent  opportunity  for  investigating  the  di 
therefore  existed.     The  Surgeon  General  of  the  Army  sent  to  I  la  ban  a 
a  board  of  Army  medical  officers  for  the  purpose  of  in\  «  -li.  ating 
yellow  fever.    This  board  was  made  up  of  the  following  Army  do.  ; 
Dr.  Reed,  the  president,  and  Drs.  Carroll,  Agramonte,  and   La/car. 
After  much  investigation  they  determined  to  study  the  relation  of  the 
mosquito  to  yellow  fever.    Their  attention  was  called  to  this  matter 
by  tne  part  that  the  mosquito  had  already  been  pro  vet  I  to  pla 
malaria  and  lilariasis,  as  mentioned  above,  and  also  by  certain  facts 
known  in  the  history  of  yellow  fever  epidemics.     Dr.  Hnlay,  a  prom- 


YELLOW   FEVER.  241 

inent  physician  of  Habana,  reasoning  from  certain  peculiarities  of 
yellow  fever  and  from  experiments  which  he  made,  had  maintained 
ifor  many  years  that  a  certain  kind  of  mosquito  in  Habana,  the  stego- 
myia,  was  the  cause  of  yellow.  fever.,.  Jout.  he  had  not  been  able  to 
; prove  it. 

DIRECTIONS    WITH   REGARD   TO    DESTROYING   MOSQUITOES. 

The  Army  board  of  which  Dr.  Reed  was  president  recognized  that 
in  Cuba,  where  they  did  their  work,  it  would  have  to  be  entirely 
evident  that  the  men  experimented  upon  could  not  geVfyellow  fever 
accidentally  in "  Habana,  :or any  where  ,ejse,  'but  only,  .if  at  all,  in  the 
t  course  of  the  experiment.  They  therefore  took  a  piece  of  unoccupied 
'ground  about-6  miles  from  Habana  and  built  -there  a  camp  of  material 
•which  could  not  have  been  infected  with  yellow  fever.  'They  then 
got  men  who  had  never  suffered  from  yellow  fever  and  placed  them  in 
these  tents.  It -was  known  that -if  a  man  exposed  to  v  el-low,  lever  was 
going  to 'have  it  the  disease'  would  develop  <m-4£3s  tkmi-«sfK"rl'ays,*aiid 
if  he  passed  through  six  days  safe  and  sound  he  was  known  to  have 
escaped  that  particular  exposure. 

The  board  therefore  argued  that  if  they  kept  their  men  in  this  camp 
for  a  period  of  two  weeks  they  would  be  safe  from  any  exposure 
which  might  have  occurred  before  their  coming  to  the  camp.  They 
also  had  to  provide  means  which  would  insure  their  men  not  leaving 
the  camp,  contracting  the  disease  outside,  and  thus  bringing  infection 
into  the  camp.  This  was  done  by  a  military  guard,  who  allowed  no 
one  to  go  out  or  come  in  without  Dr.  Reed's  permission.  Things  were 
now  so  arranged  that  if  a  mosquito  was  allowed  to  bite  a  man,  and 
yellow  fever  developed,  the  board  could  be  certain  that  the  yellow 
fever  was  due  to  the  bite  of  the  mosquito  alone.  They  did  a  great 
deal  of  experimenting  here  before  they  worked  out  all  the  details  of 
the  way  in  which  the  mosquito  actually  conveys  yellow  fever.  They 
finally  found  out  that  if  a  female  mosquito  of  one  particular  species, 
the  stegomyia,  was  applied  to  a  yellow-fever  patient  in  the  first  3 
days  of  his  sickness,  and  then  kept  from  10  to  "20  days  and  allowed 
to  bite  a  human  being  who  had  never  had  yellow  fever,  he  would 
very  generally  develop  the  disease  within  6  days  after  the  bite. 

They  also  found  out  that  this  same  man,  before  he  had  been  bitten 
by  the  yellow-fever  mosquito,  could  sleep  in  the  bed  in  which  a  patient 
had  died  of  yellow  fever,  could  be  covered  with  a  black  vomit  from  a 
yellow-fever  patient,  or  be  exposed  to  the  emanations  from  yellow 
fever  in  any  other  way,  and  as  long  as  he  was  kept  safe  from  the  bite 
of  the  mosquito  he  would  not  have  yellow  fever;  but  this  same  man, 
after  all  this  exposure,  if  afterwards  bitten  by  an  infected  yellow-fever 
mosquito,  would  very  certainly  catch  the  disease.  I  think  it  would  be 
interesting  to  give  some  of  the  details  of  the  work  by  which  this  great 
discovery  was  demonstrated. 

They  had  a  little  frame  building  built  in  this  camp  furnished  with 
jars  and  the  necessary  simple  material  for  breeding  mosquitoes.  The 
building  was  carefully  screened  and  guarded,  so  that  mosquitoes  could 
not  get  in  nor  out.  Eggs  of  this  particular  species  of  mosquito  were 
obtained  and  hatched  in  one  of  the  jars.  A  female  mosquito  was 
taken  from  the  brood  thus  hatched.  The  male  mosquito  will  not  bite, 
and  can  readily  be  distinguished  from  the  female  with  a  magnifying 
79965 °_S.  Doc.  822,  61-3 16 


•2 4'2  YKi  .  i  i:. 

glass*  by  the  fact  that  the  male  has  very  heavy  feathery  feelers  (anten- 
na) growing  from  his  head.  The  female  mosquito  selected  was  put 
into  a  small  glass  tube,  stoppered  with  a  little  cotton,  so  that  she  could 
get  air  freely  hut  not  escape,  taken  to  1  labanu.  nlaced  on  the  hand  of  a 
patient  in  the  first  three  days  of  an  attack  of  yellow  fever,  and  allowed 
to  fill  herself  with  blood.  She  was  then  brought  back  to  her  former 
home,  placed  in  a  large  glass  jar,  and  allowed  to  digest-  the  blood  she 
had  obtained.  The  jar,  covered  with  a  piece  of  mosquito  netting,  had 
in  it  a  small  saucer  with  a  little  water,  and  a  lump  or  white  sugar  was 
also  provided.  Under  these  conditions  the  mosquito  was  furnished 
with  all  the  necessities  of  life. 

So  confident  were  the  men  in  charge  of  the  mosouitoes  that  I  h 
known  them  to  put  their  hands  in  the  jars  and  let  trie  mosquitoes 
upon  them,  up  to  the  fifth  or  sixth  day  after  the  mosquito  had  bit  ten 
a  yellow-fever  patient.     The  mosquito,  you  recollect,  can  not  convey 
the  disease  till  from  12  to  20  days  have  passed  from  the  time  of  her 
biting  the  yellow-fever  case  from  which  she  becomes  infected. 

On  the  other  hand,  I  once  saw  a  party  of  12  or  15  doctors  in  the 
mosquito  room  one  day,  when  the  mosquito-bar  covering  of  the  jar 
accidentally  came  off  and  the  insects  escaped  into  the  room.  These 
doctors  had  come  from  other  countries  to  investigate  the  subject,  and 
were  not  then  convinced  that  the  mosquito  carried  yellow  1« 
Still,  they  did  not  care  to  put  the  matter  to  a  practical  test  in  their 
own  persons,  and  got  out  of  the  room  so  rapidly  that  the  wire-screen 
door  was  broken  down  during  their  exit.  It  happened  that  the  inos- 
guitoes  in  this  jar  had  never  bitten  a  yellow-fever  patient  and  were  not 
infected. 

After  the  mosquito  had  been  left  in  this  condition  for  from  10  to  20 
days,  it  was  known  that  her  saliva  was  capable  of  transmitting  the 
disease.  When  she  was  wanted  for  the  purpose  of  giving  some  hoc  ly 
yellow  fever,  a  man  would  take  a  glass  tube,  slip  his  hand  under  the 
mosquito  netting,  put  the  mouth  of  the  tube  over  the  mosquito,  and 
then  fill  the  mouth  of  the  tube  with  a  cotton  stopper,  as  above 
described.  She  would  then  be  taken  to  the  man  to  whom  it  was 
desired  to  give  yellow  fever  and  who  had  bravely  volunteered  for  the 
purpose,  the  cotton  stopper  taken  out,  the  tube  turned  upside  down 
with  its  mouth  resting  on  the  skin,  and  the  mosquito  allowed  to  set  tie. 
She  would  then  introduce  her  biting  apparatus  and  slowly  fill  her- elf 
with  blood.  But  before  she  fills  with  blood  she  injects  her  saliva  into 
the  wound,  just  as  does  the  snake  in  biting.  It  is  this  injection  of  the 
saliva  that  causes  the  swelling  and  the  burning  sensation  that  is  felt 
at  the  point  where  the  mosquito  bites  and  which  lasts  some  time  after 
she  has  finished.  The  injection  of  the  irritating  saliva  probably  has 
the  effect  of  making  it  easier  for  the  mosquito  to  get  blood. 

Now,  it  will  be  remembered  that  this  man  who  was  bitten  had  been 
kept  in  the  camp  for  two  weeks  before  he  was  bitten,  and  isolated  in 
such  a  way  that  he  could  not  possibly  have  contracted  yellow  fever. 
There  were  30  or  40  men  in  the  same  camp  under  exactly  the  same 
conditions.  Three  or  four  days  after  he  was  bitten  by  the  mosquito 
he  developed  a  well-marked  case  of  yellow  fever,  although  everybody 
else  in  the  camp  remained  well.  Dr.  Reed  and  his  fellow  workers 
therefore  very  naturally  believed  that  that  particular  mosquito 
the  man  yellow  fever.  They  repeated  this  test  12  or  15  different  times 
with  the  same  result.  NoSody  else  in  the  camp  had  yellow  fever. 


YELLOW   FEVER.  243 

Always  within  six  days  after  the  bite  of  the  mosquito  known  to  be 
infected  the  man  experimented  upon  had  yellow  fever. 

To  show  how  a  house  could  become  infected  with  yellow  fever  the 
board  conducted  the  following  experiment:  They  built  a  large  room 
and  screened  it  so  that  mosquitoes  could  not  get  in  or  out.  (When- 
ever 1  use  the  word  "screen"  here  I  mean  the  ordinary  wire  netting  or 
mosquito  bar.)  The  purpose  is  of  course  to  leave  a  perfectly  free  cir- 
culation of  air,  but  to  have  the  meshes  of  the  wire  or  mosquito  bar 
netting  so  small  that  a  mosquito  can  not  get  through.  They  then 
divided  this  room  into  two  parts  by  a  wire  netting  extending  from  top 
to  bottom,  so  that  a  mosquito  could  not  pass  from  one  side  to  the  other, 
but  at  the  same  time  leaving  the  circulation  of  air  entirely  free,  the 
desire  being  to  show  that  if  it  were  any  miasm,  or  emanation,  or  germ 
floating  in  the  air  which  caused  yellow  fever  it  could  freely  pass  from 
one  side  to  the  other  of  this  netting,  and  that  both  rooms,  as  far  as 
these  emanations  were  concerned,  were  in  the  same  condition. 

Now,  to  show  that  the  building  was  uninfected,  four  men  were  put 
in  it  who  had  never  had  yellow  fever,  two  sleeping  on  each  side  of  the 
wire  netting.  They  were  left  there  for  two  weeks  and  remained  per- 
fectly well.  Reed  then  said,  "I  am  now  going  to  infect  the  room  on 
one  side  of  this  wire  netting  with  yellow  fever  and  not  infect  the  other 
side."  He  took  the  two  men  out  of  one  side  and  liberated  a  half 
dozen  infected  female  Stegomyia  mosquitoes  on  this  side.  The  two 
men  still  slept  and  lived  on  the  uninfected  side.  He  then  put  a 
volunteer  on  the  side  with  the  mosquitoes  and  left  him  there  for  half 
an  hour,  took  him  out,  and  within  six  days  this  man  developed  yellow 
fever,  the  two  men  on  the  other  side  of  the  room  remaining  well. 

He  therefore  argued  that,  as  the  two  men  who  had  been  for  so  long 
a  time  on  one  side  of  the  wire  netting  and  remained  well  were  breath- 
ing the  same  emanations,  and  the  only  difference  was  that  there  were 
mosquitoes  on  the  infected  side  to  which  the  man  had  been  exposed 
for  half  an  hour,  it  was  very  good  proof  that  the  mosquito  was  the 
factor  which  gave  yellow  fever.  He  then  said,  "Now  that  I  have 
shown  you  a  nouse  infected  with  yellow  fever,  I  will  demonstrate 
how  it  can  be  disinfected  and  rendered  safe."  He  then  caught  his 
half  dozen  mosquitoes,  bottled  them  up  and  put  them  back  into  their 
jars,  and  announced  that  the  building  was  entirely  safe  and  unin- 
fected, put  the  two  men  back  into  the  side  which  had  been  infected, 
and  the  four  continued  to  sleep  and  live  as  safely  in  these  quarters 
as  they  had  before  the  infection. 

The  board  had  another  room  built  and  got  ah1  sorts  of  material 
infected  by  yellow-fever  patients  from  the  hospital,  clothing  worn  by 
patients  at  the  time  they  died  of  yellow  fever,  such  as  mattresses  on 
which  they  died,  soiled  in  every  possible  way,  pillows  and  pillowcases 
saturated  with  black  vomit,  and  blankets  over  which  basins  of  black 
vomit  had  been  poured;  in  short,  material  infected  by  yellow  fever  in 
every  possible  way  that  could  be  thought  of.  All  this  material  was 
placed  in  the  room,  which  was  made  close  and  tight  with  very  little 
ventilation,  so  as  to  make  the  conditions  most  favorable  for  what  was 
ordinarily  considered  the  best  way  of  insuring  the  spread  of  yellow 
fever.  Volunteers  who  had  never  had  yeUow  fever  were  placed  in 
this  room,  lived  and  slept  there  for  two  weeks  at  a  time,  wore  this 
clothing,  slept  on  these  mattresses,  under  these  sheets,  and  yet  not  a 
single  case  of  yellow  fever  was  developed  from  this  contact.  The 


•244  YKLLOU 

men  who  hail  undergone  this  exposure  were  taken  out  and  -kept  tor 
weeks  30  as  to  in-ure  that  they  had  not  contracted  yellow  fever 
from  the  exposure,  and  then  bitten  by  infected  mosquitoes.  They 
always  got  yellow  fever  from  the  bite  of  the  mosquito,  hut  never  in 
any  other  way. 

At  this  time  the  military  authorities  had  had  entire  control  of 
Habana  for  about  two  years.  An  Army  doctor  had  been  placed  in 
charge  of  the  health  department  and  given  the  mean-  and  power  to 
do  \\hat  he  thought  jno>t  likely  to  free  the  city  from  yellow  fever. 
Yello\\  lV\cr  in  Ilahana  wa-  a  disease  like  consumption  in  OalveMon 
w  Orlean>  —  always  there,  and  always  One  of  tne  principal  oauses 
of  death  in  the  city.  And  this  had  been  the  state  of  all'airs  a-  |o: 
anything  had  been  known  with  any  accuracy,  either  about  yeflow 
fever  or  about  the  health  conditions  of  Habana;  and  the-e  'tiling 
were  pretty  accurately  known  for  more  than  a  hundred  year-  imme- 
diately preceding  the  time  I  refer  to.  When  we  organized  our  health 
department,  we  believed,  as  did  everybody  el-e,  that  yellow  fever  was 
caused  by  filth,  dirt,  and  general  insanitary  conditions,  so  we  went 
to  work  doing  our  very  best  to  correct  these  conditions.  With  these 
efforts  Habana  very  rapidly  became  a  healthy  city,  as  much  so  as 
many  of  our  large  cities  in  tne  United  States,  but  yellow  fever  did  not 
seem  to  be  affected. 

The  second  year  of  our  control  yellow  fever  was  very  severe  in 
Habana,  but  did  not  attack  the  native  Cuban  because  he  was  generally 
acclimated.  Only  the  foreigner,  therefore,  was  subject  to  the  disease. 
During  the  year  1900  many  of  our  prominent  American  civilians  and 
military  officials  died  of  the  disease,  and  the  very  cleanest  and  h«-t 
parts  of  the  city  and  the  people  who  lived  best  and  took  the  be>t 
of  themselves  were  most  affected.  When  the  Army  Board  published 
their  discovery  to  the  world  the  health  department  of  Habana  r< 
nized  that  it  and  all  the  rest  of  the  world  had  been  on  the  wrong 
track  with  regard  to  yellow  fever,  and  they  determined  to  change 
their  methods  and  attack  the  mosquito  as  the  cause  of  the  disease. 

They  had  been  convinced  by  tne  work  of  the  Army  board  that  a 
human  being  could  only  get  yellow  fever  by  being  bitten  by  a  par- 
ticular kina  of  mosquito — the  stegomyia — which  had  previously 
bitten  a  man  suffering  from  yellow  fever.  They  therefore  arranged 
that  as  soon  as  a  man  sickened  with  yellow  fever  employees  from  t  he 
department  went  to  the  house  and  screened  it  with  wire  nettii. 
that  those  mosquitoes  that  were  in  the  house  could  not  get  out  and 
those  outside  could  not  get  in.  A  smudge  was  then  made  of  sulphur, 
tobacco,  or  insect  powder,  as  host  suited  to  the  circumstances,  in  the 
affected  house,  and  in  all  those  immediately  around  it.  with  the 
intention  of  killing  all  moscjuitoes  present,  liy  this  method  it  was 
hoped  that  both  the  mosquitoes  that  had  bitten  the  man  and  ca 
the  disease  would  be  killed,  and  also  those  that  had  bitten  the  man 
after  he  was  taken  >ick.  and  had  thus  become  themselves  infected 
and  able  to  spread  the  disease.  For  the  purpose  of  doinir  this 
screening  a  building  was  arranged  very  much  like  a  fire  stat  ion  in  «»ne 
of  our  cities,  where  wagons,  wire  screens,  carpenters,  and  men  with 
material  for  making  a  smudge,  were  always  kept  on  duty,  who  pro- 
ceeded at  once  to  the  place  where  a  yellow  fever  case  was  reported  to 
exist. 


YELLOW    FEVEIt.  245 

This  method  was  very  successful  in  its  results.  After  its  adoption 
very  few  cases  occurred  where  the  disease  spread  from  the  person 
infected  to  others  in  the  neighborhood.  It  was  also  determined  to 
destroy  as  many  as  possible  of  the  yellow  fever  mosquitoes  in  the 
city.  It  was  known  that  the  female  mosquito  had  to  have  water 
on  which  to  lay  her  eggs,  and  that  these  eggs  could  not  hatch  without 
water;  that  this  water  had  to  be  very  quiet  and  well  protected  for  the 
hatching  process  to  take  place ;  that  the  eggs  took  about  three  days 
to  hatch;  that  after  hatching  the  insect  had  to  live  the  life  of  a  fish 
in  this  water  for  five  or  six  days.  During  this  fish  stage  they  are 
known  as  larvae,  and  are  well  known  to  everybody  in  the  South,  for 
they  are  nothing  but  the  common  wigglers  always  found  in  standing 
rain  water  during  the  summer  months.  Now,  while  in  this  wiggler 
stage  the  insect  has  to  have  air,  and  for  this  purpose  must  every 
little  while  come  to  the  surface.  At  the  end  of  five  or  six  days  the 
wiggler  changes  into  the  full-grown  mosquito. 

It  is  known  that  this  particular  species  of  mosquito — the  stegomyia, 
or  the  yellow  fever  mosquito — lives  and  breeds  almost  altogether  in 
houses  and  in  their  immediate  neighborhood,  and  does  not  leave  the 
house  for  any  great  distance.  With  this  knowledge  of  its  life  history, 
the  department  found  it  easiest  to  destroy  the  mosquito  in  its  wiggler 
stage,  and  the  most  useful  means  in  this  direction  they  found  to  be 
the  doing  away  with  all  the  little  deposits  of  water  in  and  near  inhab- 
ited houses,  which  the  wiggler  must  have  in  order  to  develop  into  the 
mosquito.  The  methods  herein  described  were  not  settled  upon,  as 
might  appear  from  this  account,  all  at  once  and  at  the  beginning,  but 
many  other  methods  of  waging  war  against  the  mosquito  were  tried, 
found  impracticable,  and  dropped. 

With  the  object  of  doing  away  with  the  breeding  places  of  the 
yellow-fever  wiggler,  all  the  houses  and  yards  of  Habana  were  carefully 
examined  and  all  tin  cans,  empty  bottles,  and  trash  of  the  same  kind, 
which  were  generally  found  filled  with  rain  water  and  full  of  yellow 
fever  mosquito  larvae,  were  carefully  carted  off.  Then  the  necessary 
openings  in  all  cisterns  were  covered  with  mosquito  netting,  so  that 
the  mosquitoes  could  not  get  in  to  lay  their  eggs.  Among  the  poorer 
people,  who  had  only  barrels  and  other  similar  receptacles  for  rain 
water  (and  in  Habana  every  family  had  something  of  this  kind),  the 
health  department  arranged  these  necessary  receptacles  for  them  by 
placing  a  wooden  cover  on  the  barrel,  leaving  a  hole  in  the  center  of 
this  cover  for  the  entrance  of  water,  and  covering  the  hole  with  wire 
netting,  so  that  mosquitoes  could  not  get  in.  To  enable  them  to  draw 
off  the  water  without  opening  the  barrel  a  cheap  wooden  spigot  was 
placed  in  the  lower  part. 

Now,  from  the  peculiarity  of  the  wiggler,  that  he  has  to  come  to  the 
surface  of  the  water  every  few  seconds  to  get  air,  if  we  put  anything 
on  the  surface  of  the  water  that  prevents  him  getting  this  air,  he 
drowns  just  as  certainly  as  a  man  would  who  is  kept  under  the  water. 
Ordinary  kerosene  oil,  a  tablespoonful  or  two  to  a  cistern,  spreads 
over  the  surface  of  the  water  and  kills  the  wiggler  in  this  way.  He 
can  not  break  through  the  scum  of  oil  to  get  air.  But  oil  very  rapidly 
evaporates  and  has  frequently  to  be  renewed.  So  oil  was  only  used 
in  Habana  where  no  other  method  was  successful.  The  privy  pits  in 
all  the  houses  there  were  in  the  center  of  the  court,  covered  generally 
with  heavy  flagstone.  These  pits,  not  being  in  general  accessible  to  the 


246  YKLI.OW     F! 

inspectors,  had  to  be  treated  with  oil.     Once  a  month  a  couple  of 
ounces  of  oil  were  poured  into  the  pipes  leading  to  the  pit-. 

To  insure  that  these  methods  and  ordinances  were  carried  out.  the 
city  was  divided  into  districts  of  about  a  thousand  houses  each,  BO 
that  an  inspector  would  get  over  each  district  in  the  course  of  a  inont  h, 
inspect  in*:  at  the  rate  of  about  30  hou-c-  a  day.  This  inspector 
had  with  him  two  men  who  used  the  oil  as  ahove  described.  lie  had 
with  him  printed  blanks  on  which  he  entered  the  condition  of  the 
premises  as  to  w idlers.  These  reports  were  turned  in  every  night 
to  the  office  of  the  health  department  and  wero  consolidated  from  day 
today.  At  the  end  of  the  month  we  could  therefore  tell  the  condition 
of  Habana  as  to  wigglers.  At  the  first  report  on  this  subject  (I  think 
in  March,  1901)  we  found  that  we  had  in  Habana  in  the  neighbor- 
hood of  26,000  different  water  deposits  which  contained  w idlers. 
most  of  them  of  the  yellow-fever  variety. 

After  once  going  over  the  city  and  carefully  explaining  to  the 
people  the  dangers  of  allowing  wigglers  on  their  premises,  and  after 
having  fixed  up  for  the  poor  all  the  water  barrels  which  they  were 
obliged  to  keep  for  holding  their  ram  water,  the  mayor  of  the  city 
issued  an  ordinance  stating  that  anybody  who  bred  wigglers  on  his 
premises  would  be  fined  $10.  These  two  methods  of  destroying 
yellow  fever  mosquitoes,  namely,  that  of  killing  the  grown  mosquito 
in  the  neighborhood  of  every  yellow  fever  patient  with  a  smudge  and 
of  looking  after  the  wigglers  hi  all  rain  water  deposits  about  the  house, 
were  steadily  enforced  during  the  year  1901.  The  results  were  bet  t  er 
than  we  had  dared  to  hope.  Few  cases  occurred  in  which  yellow 
fever  spread  from  a  case  cared  for  in  this  wav.  Yellow  fever  rapidly 
decreased,  and  on  September  28,  1901,  the  last  case  of  yellow  1 
occurred  in  Habana,  and  since  that  time — now  more  than  two  years — 
not  a  single  new  case  has  developed  in  the  city. 

There  were  still,  of  course,  a  great  many  yellow  fever  mosquitoes 
in  Habana,  but  these  methods  of  destroying  the  wigglers  had  greatly 
decreased  the  numbers  of  mosquitoes.  The  report  of  January,  1 
after  about  ten  months  of  this  mosquito  work,  showed  that  within 
the  city  limits  less  than  300  premises  had  wigglers  upon  them.  This 
I  think  a  very  fair  measure  of  the  results  accomplished  by  one  year's 
work,  namely,  that  the  number  of  deposits  containing  wigglers  had 
been  decreased  from  about  26,000  to  about  300. 

I  think  it  is  evident  that  tne  disappearance  of  yellow  fever  from 
Habana  was  due  solely  to  this  mosquito  work.  Remember  that  it 
was  an  every-day  disease  in  Habana,  and  had  been  so  for  more  than 
a  hundred  years,  just  as  consumption  is  in'  New  Orleans,  a  city  of 
about  the  same  size  as  Habana.  Now,  if  some  method  should  be 
adopted  against  consumption  in  New  Orleans,  and  systematically 
put  in  operation  in  the  city  against  that  disease,  and  at  the  end  of  a 
year  it  could  be  shown  that  no  new  cases  of  consumption  were  occur- 
ring in  New  Orleans,  and  at  the  end  of  two  years  and  a  half  it  could 
be  further  shown  that  under  the  continuance  of  the  same  measures 
the  disease  had  entirely  disappeared  from  the  city,  and  no  new  cases 
had  occurred,  I  should  think  that  we  would  all  be  at  once  convinced 
that  the  disappearance  of  consumption  from  New  Orleans  was  due  to 
the  efficacy  of  the  measures  adopted. 

In  Habana,  even  now,  a  case  or  two  of  yellow  fever  comes  in  every 
month  from  Mexico  and  other  infected  regions  which  have  a  con- 


YELLOW   FEVER.  247 

siderable  trade  with  Habaiia.     The  ships  are  carefully  inspected  by 
the  quarantine  authorities,  just  as  is  done  in  our  country.     If  a 

Eerson  sick  of  yellow  fever,  or  suspected  yellow  fever,  is  discovered, 
e  is  landed  at  the  city  wharf,  in  the  heart  of  the  business  district, 
placed  in  an  ambulance,  carried  to  the  yellow  fever  hospital,  which 
is  well  within  the  city  limits,  and  treated  there.  The  only  precau- 
tion taken  is  to  see  that  Habana  mosquitoes  do  not  get  an  oppor- 
tunity to  bite  him.  The  authorities  at  Habana  thoroughly  believe 
that  if  they  can  prevent  mosquitoes  from  biting  a  yellow  fever  patient 
the  city  will  be  entirely  safe  in  handling  him  and  taking  care  of  him. 

In  1901,  during  the  height  of  the  yellow  fever  work  at  Habana,  a 
town  of  about  5,000  inhabitants,  some  12  miles  from  the  city,  became 
badly  infected  with  yellow  fever.  This  town,  Santiago  de  las  Vegas, 
was  practically  a  suburb  of  Habana,  and  the  business  communication 
with  the  city  was  very  intimate.  We  found  that  people  who  were 
working  at  Santiago  de  las  Vegas  were  constantly  getting  sick  of 
yellow  fever,  and  as  soon  as  they  found  themselves  sick  would  come 
into  Habana  to  the  homes  of  their  friends  and  relatives  to  be  taken 
care  of.  In  order  to  do  away  with  this  source  of  danger,  a  large  force 
of  men  was  put  at  work  at  Las  Vegas,  on  the  lines  above  described. 
The  whole  town  was  systematically  gone  through  from  house  to  house, 
and  at  the  end  of  about  six  weeks  of  this  work  the  disease  was  entirely 
wiped  out  and  we  had  no  more  trouble  with  infection  from  Las  Vegas. 
1  mention  this  as  showing  the  possibility  of  taking  a  small  town  and 
getting  rid  of  the  disease  rapidly  by  mosquito  work. 

We  had  other  mosquito  work  going  on  in  the  suburbs  of  Habana, 
among  the  truck  gardens  and  irrigated  fields  where  grass  was  grown. 
But  the  yellow-fever  mosquito  does  not  breed  to  any  great  extent  in 
such  places,  and  I  do  not  think  this  work  had  much  effect  upon  the 
yellow  fever.  But  malaria,  as  I  have  above  mentioned,  is  also  carried 
exclusively  by  a  mosquito  named  the  "  anopheles."  Now,  this  malarial 
mosquito  likes  to  breed  in  places  where  there  are  little  puddles  of 
water,  cow  tracks,  horse  tracks,  and  similar  depressions  in  grassy 
ground,  and  the  work  in  the  suburbs  had  its  principal  effect  upon  this 
mosquito.  It  was  not  desirable  to  stop  irrigation,  as  the  livelihood  of 
all  these  small  farmers  depend  upon  it,  but  by  taking  advantage  of 
the  fact  that  a  deposit  of  water  had  to  remain  undisturbed  at  least  10 
days  to  breed  a  mosquito,  we  could  allow  them  to  irrigate  freely,  pro- 
vided the  water  did  not  remain  longer  than  a  week.  The  health  de- 
partment had  all  this  area  arranged  with  shallow,  superficial  ditches 
which  would  not  interfere  with  irrigation,  but  would  allow  rapid 
drainage  when  the  water  was  taken  off.  All  pools  and  puddles  which 
had  no  economic  use  were  kept  drained,  and  ditches  and  streams  kept 
clean  of  grass  and  obstructions. 

After  once  getting  the  country  cleaned  up  at  public  expense,  and 
the  matter  explained  to  the  farmer,  he  was  fined  in  the  same  way  as 
the  householder  in  the  built-up  portion  of  the  city,  if  wigglers  were 
discovered  on  his  premises.  While  I  do  not  think  that  these  measures 
aided  us  particularly  in  yellow  fever,  they  had  a  marked  effect  upon 
malaria.  In  1900,  the  year  before  the  mosquito  work  commenced,  we 
had  in  Habana  325  deaths  from  malaria.  During  1901,  the  year  in 
which  mosquito  work  was  commenced,  we  had  151  deaths  from 
malaria.  In  1902,  the  second  year  of  mosquito  work,  Dr.  Carlos 
Finlay,  the  health  officer  of  Cuba,  reported  77  deaths  from  malaria  in 


248  :  »^'   1'i 

Habana,  and  up  to  the  1st  o!'  No\  ember  in  1  !»():>.  the  third  year  of 
mosquito  work.  Dr.  Finlay  reported  l.">  deaths  from  malaria. 

This  mosquito  work  of  the  Hnhana  health  department,  1  hold, 
demonstrates  the  practicability  of  eliminating  in  the  Tropics  the  two 
diseases  malaria  and  yellow  fever,  and  I  believe  if  the  attention  of  the 
people  at  large  in  our  own  country  were  generally  attracted  to  the 
danger  of  transmitting  disease  by  the  mosquito,  and  the  practicability 
of  destroying  them,  we  could  very  generally  eliminate  these  two 
diseases  from  our  own  country. 

And  now  to  the  reason  for  writing  this  article.  I  thought  an  account 
of  the  relations  of  mosauitoes  to  disease,  given  in  simple  terms,  readily 
understood  by  t  hose  wlio  are  not  doctors,  might  held  people  generally 
in  making  aii  attempt  to  get  rid  of  mosquitoes,  each  man  about  his 
own  house.  I  will  now  proceed  to  make  suggestions  in  this  direction. 
And  in  order  to  make  myself  entirely  clear  will  repeat  a  good  deal, 
and  enlarge  upon  what  I  have  already  said. 

The  work  of  the  Army  medical  board  of  which  Maj.  Walter  Keed 
was  president,  showing  that  a  particular  species  of  mosquito  was  the 
only  means  of  transmitting  yellow  fever,  is  now  pretty  generally 
accepted  by  all  the  scientific  world.  Based  upon  this  knowledge, 
certain  methods  were  adopted  by  the  Army  medical  officers  in  Haba  n  a , 
Cuba,  which  resulted  in  eradicating  yellow  fever  from  that  city. 
During  the  fall  of  1903  yellow  fever  was  introduced  from  Mexico  and 
became  quite  widely  spread  through  western  Texas.  It  is  thought 
that  a  few  general  rules,  based  upon  the  knowledge  acquired  by  tho 
Army  board  and  the  experience  of  the  Army  medical  officers  in  I  labana. 
may  be  of  use  in  assisting  individuals  and  towns  in  freeing  themselves 
from  infected  mosquitoes  during  the  present  winter  and  coining 
spring.  Otherwise,  it  seems  highly  probable  that  yellow  fever,  at 
some  point  in  Texas,  will  again  develop  as  the  warm  weather  comes  on. 
This  would  come  about  from  the  fact  that  the  infected  mosquito  can 
very  readily  live  through  the  winter  in  the  latitude  of  Laredo. 

As  yellow  fever  can  only  be  spread  by  a  particular  species  of  mos- 
quito, it  follows  that  if  there  are  none  of  these  mosquitoes  about, 
yellow  fever  can  not  spread.  The  danger  in  Texas  is  that  the  steg- 
omyia  mosquitoes,  that  have  bitten  people  with  yellow  fever,  will  live 
through  the  winter  and  spread  another  epidemic  as  the  warm  weat  her 
comes  on  by  biting  people  who  have  not  had  the  disease.  This  mos- 
quito, from  its  nature,  stays  immediately  about  the  house  and  in  the 
rooms,  and  seldom  or  never  wanders  far.  It  was  found  in  I  labana 
that  by  destroying  all  the  mosquitoes  in  each  house  where  yellow 
fever  occurred  the  disease  was  always  stopped  in  that  particular 
neighborhood.  It  is  probable,  therefore,  that  if  each  householder  in 
whose  house  yellow  fever  has  occurred  during  the  past  fall  will 
destroy  all  the  mosquitoes  in  his  house  he  will  be  free  from  the  old 
infection  next  spring.  This  can  readily  be  done  by  closing  the  room 
and  making  a  smudge  in  it  of  sulphur  or  tobacco.  Care  should  be 
taken  to  paste  all  the  cracks  up  with  paper,  so  that  the  smudge  will 
be  confined  to  the  room  fumigated,  and  the  pan  in  which  t  ho  smudge 
is  made  placed  on  a  little  earth,  so  that  it  can  not  set  the  floor  on  fire. 

With  sulphur,  about  a  pound  to  a  room  10  feet  square,  should  be 
used,  and  with  tobacco,  about  half  a  pound.  To  start  the  sulphur 
burning  a  couple  of  tablespoonfuls  of  alcohol  should  be  poured  on 
before  applying  the  match.  Sulphur  should  be  used  unless  the  room 


YELLOW  FEVER.  249 

contains  valuable  material  which  might  be  injured  by  it.  The  fumes 
of  tobacco  hurt  nothing,  but  leave  a  disagreeable  odor.  The  fumes 
of  ordinary  Persian  insect  powder  hurt  nothing  and  leave  no  odor,  but 
it  does  not  always  kill  the  mosquitoes  and  care  has  to  be  taken  to 
sweep  them  up  afterwards.  A  couple  of  hours  will  be  time  enough  to 
keep  the  room  closed.  After  that  time  it  can  be  opened,  aired,  and 
occupied.  In  towns,  this  method  should  be  carefully  carried  out  dur- 
ing the  winter  by  the  town  authorities.  Not  only  the  houses  in  which 
yellow  fever  is  known  to  have  occurred,  but  every  house  in  the  infected 
town  should  be  treated  in  this  way.  We  found  in  Habana  that  a  squad 
of  five  men,  under  intelligent  direction,  could  easily  fumigate  a  10- 
room  house  in  two  hours.  It  should  be  arranged  so  that  the  whole  of 
the  infected  town  should  be  gone  over  before  the  1st  of  April. 

The  above  directions  cover  the  points  with  regard  to  killing  infected 
mosquitoes,  and  thereby  preventing  the  liability  of  a  new  epidemic 
next  summer  from  the  old  mosquitoes  left  over  from  last  year.  But 
it  is  even  more  important  to  prevent  the  breeding  of  a  new  crop  of 
stegomyia  mosquitoes,  and  this  can  be  very  readily  done  without  very 
great  effort. 

The  female  stegomyia  mosquito  always  seeks  some  small  body  of 
well-protected  fresh  water  in  which  to  lay  her  eggs.  On  the  surface 
of  this  water  she  lays  about  60  or  70  eggs.  These,  in  warm  weather, 
in  three  days  hatch  out  into  the  ordinary  wiggler,  and  the  wiggler  in 
five  or  six  days  develops  into  the  full-grown  mosquito.  From  the 
laying  of  the  egg  to  the  development  of  the  full-grown  mosquito  takes 
about  eight  days  in  hot  weather.  Water  is  as  necessary  to  the  insect 
as  it  is  to  a  fish.  It  is  essentially  a  water  insect  during  this  period, 
though  it  is  an  air-breathing  insect,  too,  and  has  to  come  to  the  surface 
of  the  water  every  few  seconds  to  get  air. 

As  I  stated  above,  the  stegomyia  seeks  particularly  deposits  of  clean 
water,  and  is  essentially  a  house  mosquito,  breeding  either  in  the 
house  or  very  close  to  it,  in  such  places  as  cisterns  and  rain-water  bar- 
rels, and  in  anything  likely  to  catch  and  retain  rain  water,  such  as  old 
bottles  or  cans,  or  gutters  under  the  roofs  of  houses,  etc.  Now,  if 
every  householder  will  give  a  little  attention  to  see  that  there  are  no 
such  deposits  about  his  house,  he  will  be  free  from  the  stegomyia  mos- 
quito, and  no  one  will  contract  yellow  fever  in  his  house,  even  if  cases 
are  introduced  into  it  from  elsewhere.  If  necessity  obliges  him  to 
keep  a  cistern  or  barrels  of  rain  water,  if  he  will  arrange  the  receptacle 
so  that  the  mosquito  can  not  get  in  to  lay  her  eggs,  it  will  be  entirely 
safe.  In  the  cistern  this  can  be  done  by  covering  the  top  tightly,  with 
the  exception  of  a  hole  for  ventilation,  and  one  for  the  entrance  of  the 
water,  and  these  two  holes  should  be  covered  with  wire  netting.  The 
netting  should  be  not  larger  than  16  meshes  to  the  inch.  A  larger 
mesh  than  this  will  allow  the  smaller  size  of  stegomyia  to  pass  through. 

Water  barrels  can  be  arranged  in  the  same  way,  a  tight-fitting  top 
put  on,  with  a  wire  mesh  over  the  hole  for  the  entrance  of  the  water, 
and  a  cheap  spigot  put  in  the  bottom  for  drawing  off  water.  If  he 
finds  wigglers  in  any  of  the  vessels  of  water  which  he  is  obliged  to 
keep,  he  can  know  that  his  coyer  is  imperfect,  and  that  the  female 
mosquito  has  gotten  in  there  in  some  way  to  lay  her  eggs.  Small 
deposits  about  the  yard  and  in  the  immediate  neighborhood  should  be 
swept  out  or  drained  away.  A  deposit  of  water  in  Texas  would  have 
to  stand  at  least  10  days  to  breed  a  mosquito.  For  this  reason,  if  the 


250  YKLl.ou     PEVRB, 

householder  is  not  able  to  arrange  his  water  vessels  as  above  sug- 
gested he  could  avoid  breeding  steiromy  in  mosquitoes  by  having  t  hose 
vessels  emptied  once  a  week.  But  if  tlie  method  of  emptying  is  used, 
the  larvte  should  be  carefully  washed  out  or  the  vessel  K-i't  to  stand 
empty  for  more  than  an  hour.  If  this  precaution  is  not  taken,  a  con- 
siderable number  of  the  larvae  will  he  left  adherent  to  the  bottom  and 
sides  and  will  live  if  the  vessel  is  at  once  Milled.  Kerosene  oil  is 
fatal  to  the  larvae  if  two  or  three  tablespoonfuls  are  spread  over  the 
surface  of  the  water. 

As  I  said  before,  the  larvae  have  to  come  to  the  surface  every  few 
:ids  to  get  air,  and  as  they  are  unable  to  break  through  the  1ilm 
of  oil  they  die  of  suffocation,  out  the  oil  evaporates  very  rapidly  and 
should  be  renewed  every  week.  Much  the  better  method  is  cither  to 
get  rid  of  the  deposit  of  water  or  protect  it  in  the  above-mentioned 
manner.  Oil  should  only  be  relied  upon  in  treating  deposits  in  a 
building  or  its  immediate  neighborhood  which  can  not  be  man  aired  in 
one  of  the  above-mentioned  methods.  Privy  pits  which  contain  water 
were  the  only  places  in  Habana  in  which  we  habitually  resorted  to  oil. 

In  towns  these  methods  should  be  enforced  by  regular  and  syste- 
matic inspections.  In  most  towns  there  are  ordinances  against  pigs 
and  pigsties.  A  hog  is  considerably  larger  than  a  mosquito  wiggler, 
but  with  a  little  care  an  inspector  will  soon  learn  to  discover  the  wig- 
gle rs  almost  as  easily  as  the  hogs.  And  the  householder  should  be 
taught  that  the  wiggler  causes  a  great  deal  more  annoyance  to  himself 
and  his  neighbors  than  the  hog  does,  and  is  infinitely  more  dangerous 
to  health.  And  the  ordinances  should  hold  the  householder  as  strictly 
to  account  for  breeding  wigglers  on  his  premises  as  for  having  a  pigsty 
with  a  litter  of  pigs.  The  larger  deposits,  a  hundred  yards  or  more 
away  from  the  house,  such  as  small  ponds  and  swampy  places,  while 
breeding  mosquitoes  that  cause  a  great  deal  of  annoyance,  will  not 
breed  the  stegomyia  to  an  extent  sufficient  to  be  dangerous  to  the 
house.  They  should  be  managed  by  the  town  authorities  on  the  same 
general  principles — to  drain  wherever  possible. 


